MMS Observations of Multiscale Hall Physics in the Magnetotail. Issue 17 (5th September 2019)

• Record Type: Journal Article
• Authors: Alm, Love; André, Mats; Graham, Daniel B.; Khotyaintsev, Yuri V.; Vaivads, Andris; Chappell, Charles. R.; Dargent, Jérémy; Fuselier, Stephen A.; Haaland, Stein; Lavraud, Benoit; Li, Wenya; Tenfjord, Paul; Toledo‐Redondo, Sergio; Vines, Sarah K.
• Is Part Of: Geophysical research letters. Volume 46:Issue 17/18(2019)
• Page Start: 10230
• Page End: 10239
• Publication Date: 2019-09-05
• Subjects: cold ions -- Hall physics -- reconnection -- multiscale -- MMS -- magnetotail; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1029/2019GL084137
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: We present Magnetospheric Multiscale mission (MMS) observations of Hall physics in the magnetotail, which compared to dayside Hall physics is a relatively unexplored topic. The plasma consists of electrons, moderately cold ions ( T ∼1.5 keV) and hot ions ( T ∼20 keV). MMS can differentiate between the cold ion demagnetization region and hot ion demagnetization regions, which suggests that MMS was observing multiscale Hall physics. The observed Hall electric field is compared with a generalized Ohm's law, accounting for multiple ion populations. The cold ion population, despite its relatively high initial temperature, has a significant impact on the Hall electric field. These results show that multiscale Hall physics is relevant over a much larger temperature range than previously observed and is relevant for the whole magnetosphere as well as for other astrophysical plasma. Key Points: MMS multispacecraft observation of Hall electric fields during a deep partial plasma sheet crossing Mixing of hot (20 keV) and moderately cold (1.5 keV) ions generate multiscale Hall electric fields Electron and cold/hot ion demagnetization boundaries are observed near their predicted locations