Low-frequency wave activity related to dipolarization fronts detected by MMS in the magnetotail

Olivier Le Contel (1) , Alessandro Retinò (1) , Hugo Breuillard (1) , Laurent Mirioni (1) , A. Roux (1) , Thomas Chust (1) , A. Chasapis (1) , B. Lavraud (2) , P. A. Lindqvist (3) , Y. V. Khotyaintsev (4) , A. Vaivads , H. Fu , G. T. Marklund , R. Nakamura , J. L. Burch , R. B. Torbert , T. E. Moore , R. Ergun , K. A. Goodrich , J. Needell , M. Chutter , D. Rau , I. Dors , C. T. Russell , W. Magnes , R. J. Strangeway , G. Le , K. R. Bromund , F. Plaschke , D. Fischer , H. K. Leinweber , B. J. Anderson , M. R. Argall , J. A. Slavin , L. Kepko , W. Baumjohann , C. J. Pollock , B. Mauk , S. A. Fuselier

1 LPP - Laboratoire de Physique des Plasmas
2 IRAP - Institut de recherche en astrophysique et planétologie
3 KTH - KTH Royal Institute of Technology [Stockholm]
4 IRF - Swedish Institute of Space Physics [Uppsala / Kiruna]

Dipolarization fronts are often associated to reconnection jets in the magnetotail current sheet and are sites of important energy dissipation and particle energization. Since the launch on March 12th and until the 9th of July 2015, the MMS constellation has been moving from dawn to dusk in a string of pearls formation. Although particle instruments were rarely operating and only FIELDS instrument suite was often gathering data, the MMS spacecraft have detected numerous dipolarization fronts, in particular on May 15th. Since 9th of July, the MMS evolved into a tetrahedral configuration with an average inter-satellite distance of 160 km and was still able to detect dipolarization fronts in the dusk magnetotail. As the Larmor radius of thermal protons is about 500 km in this region and dipolarization fronts have a typical thickness of the order of the Larmor radius, such a separation allows us to investigate in detail the microphysics of dipolarization fronts. In this study, we focus in particular on low-frequency electromagnetic wave activity related to the fronts and discuss possible mechanisms of particle heating and acceleration both at large scales (string of pearls configuration) and at kinetic scales (tetrahedral configuration).

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

Olivier Le Contel, Alessandro Retinò, Hugo Breuillard, Laurent Mirioni, A. Roux, et al.. Low-frequency wave activity related to dipolarization fronts detected by MMS in the magnetotail. American Geophysical Union, Fall Meeting 2015, Dec 2015, San Francisco, California, United States. pp.SM41I-05. ⟨hal-02800150⟩