Electron Jet Detected by MMS at Dipolarization Front

C. M. Liu , H.S. Fu , A. Vaivads , Y. V. Khotyaintsev , D. J. Gershman (1) , K.-J. Hwang , Z. Z. Chen , D. Cao , Y. Xu , J. Yang , F. Z. Peng , S. Y. Huang , J. L. Burch , B. L. Giles , R. E. Ergun , C. T. Russell , P.-A. Lindqvist (2) , Olivier Le Contel (3)

1 GSFC - NASA Goddard Space Flight Center
2 Alfven Laboratory
3 LPP - Laboratoire de Physique des Plasmas

Using MMS high-resolution measurements, we present the first observation of fast electron jet (V_e 2,000 km/s) at a dipolarization front (DF) in the magnetotail plasma sheet. This jet, with scale comparable to the DF thickness ( 0.9 d_i), is primarily in the tangential plane to the DF current sheet and mainly undergoes the E × B drift motion; it contributes significantly to the current system at the DF, including a localized ring-current that can modify the DF topology. Associated with this fast jet, we observed a persistent normal electric field, strong lower hybrid drift waves, and strong energy conversion at the DF. Such strong energy conversion is primarily attributed to the electron-jet-driven current (E s j_e ≈ 2 E s j_i), rather than the ion current suggested in previous studies.

Domaines: Astrophysique [astro-ph]; Physique des plasmas [physics.plasm-ph]

C. M. Liu, H.S. Fu, A. Vaivads, Y. V. Khotyaintsev, D. J. Gershman, et al.. Electron Jet Detected by MMS at Dipolarization Front. Geophysical Research Letters, 2018, 45 (2), pp.556-564. ⟨10.1002/2017GL076509⟩. ⟨hal-01895682⟩