Imperial College London
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Professor Jonathan P. Eastwood

Faculty of Natural Sciences, Department of Physics

Professor of Space Physics
 
 
 
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Contact

 

jonathan.eastwood Website

 
 
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Assistant

 

Mr Luke Kratzmann +44 (0)20 7594 7770

 
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Location

 

Huxley BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Stawarz:2021:10.1029/2020ja028447,
author = {Stawarz, JE and Matteini, L and Parashar, TN and Franci, L and Eastwood, JP and Gonzalez, CA and Gingell, IL and Burch, JL and Ergun, RE and Ahmadi, N and Giles, BL and Gershman, DJ and Le, Contel O and Lindqvist, P and Russell, CT and Strangeway, RJ and Torbert, RB},
doi = {10.1029/2020ja028447},
journal = {Journal of Geophysical Research: Space Physics},
pages = {1--14},
title = {Comparative analysis of the various generalized Ohm's law terms in magnetosheath turbulence as observed by magnetospheric multiscale},
url = {http://dx.doi.org/10.1029/2020ja028447},
volume = {126},
year = {2021}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Decomposing the electric field (E) into the contributions from generalized Ohm's law provides key insight into both nonlinear and dissipative dynamics across the full range of scales within a plasma. Using highresolution, multispacecraft measurements of three intervals in Earth's magnetosheath from the Magnetospheric Multiscale mission, the influence of the magnetohydrodynamic, Hall, electron pressure, and electron inertia terms from Ohm's law, as well as the impact of a finite electron mass, on the turbulent E spectrum are examined observationally for the first time. The magnetohydrodynamic, Hall, and electron pressure terms are the dominant contributions to E over the accessible length scales, which extend to scales smaller than the electron inertial length at the greatest extent, with the Hall and electron pressure terms dominating at subion scales. The strength of the nonideal electron pressure contribution is stronger than expected from linear kinetic Alfvén waves and a partial antialignment with the Hall electric field is present, linked to the relative importance of electron diamagnetic currents in the turbulence. The relative contribution of linear and nonlinear electric fields scale with the turbulent fluctuation amplitude, with nonlinear contributions playing the dominant role in shaping E for the intervals examined in this study. Overall, the sum of the Ohm's law terms and measured E agree to within ∼ 20% across the observable scales. These results both confirm general expectations about the behavior of E in turbulent plasmas and highlight features that should be explored further theoretically.
AU  - Stawarz,JE
AU  - Matteini,L
AU  - Parashar,TN
AU  - Franci,L
AU  - Eastwood,JP
AU  - Gonzalez,CA
AU  - Gingell,IL
AU  - Burch,JL
AU  - Ergun,RE
AU  - Ahmadi,N
AU  - Giles,BL
AU  - Gershman,DJ
AU  - Le,Contel O
AU  - Lindqvist,P
AU  - Russell,CT
AU  - Strangeway,RJ
AU  - Torbert,RB
DO  - 10.1029/2020ja028447
EP  - 14
PY  - 2021///
SN  - 2169-9380
SP  - 1
TI  - Comparative analysis of the various generalized Ohm's law terms in magnetosheath turbulence as observed by magnetospheric multiscale
T2  - Journal of Geophysical Research: Space Physics
UR  - http://dx.doi.org/10.1029/2020ja028447
UR  - https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JA028447
UR  - http://hdl.handle.net/10044/1/85047
VL  - 126
ER  -
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