Published in

European Geosciences Union, Annales Geophysicae, 8(33), p. 1031-1036, 2015

DOI: 10.5194/angeo-33-1031-2015

Links

Tools

Export citation

Search in Google Scholar

Observation of a new type of low-frequency waves at comet 67P/Churyumov-Gerasimenko

Journal article published in 2015 by I. Richter, C. Koenders, H.-U. Auster, D. Fruehauff, D. Frühauff ORCID, C. Goetz, C. Götz ORCID, P. Heinisch ORCID, C. Perschke, U. Motschmann, B. Stoll, Kathrin Altwegg, J. Burch, C. M. Carr, E. Cupido and other authors.
This paper is made freely available by the publisher.
This paper is made freely available by the publisher.

Full text: Download

Green circle
Preprint: archiving allowed
Upload
Green circle
Postprint: archiving allowed
Upload
Green circle
Published version: archiving allowed
Upload
Policy details
Data provided by SHERPA/RoMEO

Abstract

We report on magnetic field measurements made in the innermost coma of 67P/Churyumov-Gerasimenko in its low activity state. Quasi-coherent, large-amplitude ($δ B/B ∼ 1$), compressional magnetic field oscillations at $∼$ 40 mHz dominate the immediate plasma environment of the nucleus. This differs from previously studied comet-interaction regions where waves at the cometary ion gyro-frequencies are the main feature. Thus classical pick-up ion driven instabilities are unable to explain the observations. We propose a cross-field current instability associated with newborn cometary ion currents as a possible source mechanism. ; Comment: 6 pages, 3 Figures