Kinetic evidence of magnetic reconnection due to Kelvin-Helmholtz waves

W. Li (1) , M. André (1) , Yu. V. Khotyaintsev (1) , A. Vaivads (1) , D. B. Graham (1) , S. Toledo-Redondo (2) , Pierre Henri (3) , C. Norgren (1) , Chen Wang (4) , B. B. Tang (4) , B. Lavraud (5) , Y. Vernisse (5) , D. L. Turner (6) , J. Burch (7) , R. Torbert (8) , W. Magnes (9) , C. T. Russell (10) , J. B. Blake (6) , B. Mauk (11) , B. Giles (12) , C. Pollock (13) , J. Fennell (14, 15) , A. Jaynes (16) , L. A. Avanov (17) , J. C. Dorelli (17) , D. J. Gershman (17) , W. R. Paterson (17) , Y. Saito (18) , R. J. Strangeway (19)

1 IRF - Swedish Institute of Space Physics [Uppsala / Kiruna]
2 ESA - Agence Spatiale Européenne = European Space Agency
3 LPC2E - Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
4 NSSC - National Space Science Center [Beijing]
5 IRAP - Institut de recherche en astrophysique et planétologie
6 The Aerospace Corporation
7 Space Science Division [San Antonio]
8 UNH - University of New Hampshire
9 IWF - Space Research Institute of Austrian Academy of Sciences
10 IGPP - Institute of Geophysics and Planetary Physics [Los Angeles]
11 APL - Johns Hopkins University Applied Physics Laboratory [Laurel, MD]
12 NASA Headquarters
13 Denali Scientific
14 Mission Research Corp.
15 BU - Boston University [Boston]
16 LASP - Laboratory for Atmospheric and Space Physics [Boulder]
17 GSFC - NASA Goddard Space Flight Center
18 ISAS - Institute of Space and Astronautical Science
19 EPSS - Department of Earth, Planetary and Space Sciences [Los Angeles]

The Kelvin-Helmholtz (KH) instability at the Earth's magnetopause is predominantly excited during northward interplanetary magnetic field (IMF). Magnetic reconnection due to KH waves has been suggested as one of the mechanisms to transfer solar wind plasma into the magnetosphere. We investigate KH waves observed at the magnetopause by the Magnetospheric Multiscale (MMS) mission; in particular, we study the trailing edges of KH waves with Alfvénic ion jets. We observe gradual mixing of magnetospheric and magnetosheath ions at the boundary layer. The magnetospheric electrons with energy up to 80 keV are observed on the magnetosheath side of the jets, which indicates that they escape into the magnetosheath through reconnected magnetic field lines. At the same time, the low-energy (below 100 eV) magnetosheath electrons enter the magnetosphere and are heated in the field-aligned direction at the high-density edge of the jets. Our observations provide unambiguous kinetic evidence for ongoing reconnection due to KH waves.

Domaines: Géophysique [physics.geo-ph]

W. Li, M. André, Yu. V. Khotyaintsev, A. Vaivads, D. B. Graham, et al.. Kinetic evidence of magnetic reconnection due to Kelvin-Helmholtz waves. Geophysical Research Letters, 2016, 43 (11), pp.5635-5643. ⟨10.1002/2016GL069192⟩. ⟨insu-01352463⟩