Extremely Low-Frequency Waves Inside the Diamagnetic Cavity of Comet 67P/Churyumov-Gerasimenko - INSU - Institut national des sciences de l'Univers Access content directly
Journal Articles Geophysical Research Letters Year : 2018

Extremely Low-Frequency Waves Inside the Diamagnetic Cavity of Comet 67P/Churyumov-Gerasimenko

Abstract

The European Space Agency/Rosetta mission to comet 67P/Churyumov-Gerasimenko has provided several hundred observations of the cometary diamagnetic cavity induced by the interaction between outgassed cometary particles, cometary ions, and the solar wind magnetic field. Here we present the first electric field measurements of four preperihelion and postperihelion cavity crossings on 28 May 2015 and 17 February 2016, using the dual-probe electric field mode of the Langmuir probe (LAP) instrument of the Rosetta Plasma Consortium. We find that on large scales, variations in the electric field fluctuations capture the cavity and boundary regions observed in the already well-studied magnetic field, suggesting the electric field mode of the LAP instrument as a reliable tool to image cavity crossings. In addition, the LAP electric field mode unravels for the first time extremely low-frequency waves within two cavities. These low-frequency electrostatic waves are likely triggered by lower-hybrid waves observed in the surrounding magnetized plasma.
Fichier principal
Vignette du fichier
Madsen_et_al-2018-Geophysical_Research_Letters.pdf (1.5 Mo) Télécharger le fichier
Origin : Publisher files allowed on an open archive
Loading...

Dates and versions

insu-01897767 , version 1 (24-10-2018)

Identifiers

Cite

B. Madsen, C. Wedlund, A. Eriksson, C. Goetz, T. Karlsson, et al.. Extremely Low-Frequency Waves Inside the Diamagnetic Cavity of Comet 67P/Churyumov-Gerasimenko. Geophysical Research Letters, 2018, 45 (9), pp.3854 - 3864. ⟨10.1029/2017GL076415⟩. ⟨insu-01897767⟩
54 View
76 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More