Volume 638, June 2020
|Number of page(s)||11|
|Section||Planets and planetary systems|
|Published online||24 June 2020|
Plasma characterization at comet 67P between 2 and 4 AU from the Sun with the RPC-MIP instrument
Laboratoire Plasma et Conversion d’Energie (LAPLACE), Université de Toulouse, CNRS,
2 Laboratoire de Physique et Chimie de l’Environnement et de l’Espace (LPC2E), CNRS, 45071 Orléans, France
3 Laboratoire Lagrange, OCA, CNRS, UCA, Nice, France
4 Laboratory for Atmospheric and Space Physics (LASP), University of Colorado Boulder 3665 Discovery Drive, Boulder, CO 80303, USA
5 Institute for Modeling Plasma, Atmospheres and Cosmic Dust, NASA/SSERVI, CA 94035, USA
6 Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles à Saint Quentin, 78280 Guyancourt, France
Accepted: 30 April 2020
The plasma of comet 67P/Churyumov-Gerasimenko is analyzed based on the RPC-MIP mutual impedance probe data of the Rosetta mission. Numerical simulations of the RPC-MIP instrumental response considering two populations of electrons were fit on experimental responses acquired from January to September 2016 to extract the electron densities and temperatures. A time-tracking of the plasma parameters was performed, leading to the identification of a cold and a warm population of electrons during the period of interest. The respective densities and temperatures lie in the ranges [100; 1000] cm−3 and [0.05; 0.3] eV for the cold electrons and in the ranges [50; 500] cm−3 and [2; 10] eV for the warm electrons. Warm electrons most of the time made up between 10 and 30% of the whole population, while the temperature ratio between warm and cold electrons lay mostly between 30 and 70 during the period we studied. The fluctuation range of the plasma parameters, that is, the electron densities and temperatures, appears to have remained rather constant during the last nine months of the mission. We take the limitations of the instrument that are due to the experimental noise into account in our discussion of the results.
Key words: plasmas / comets: individual: 67P/Churyumov-Gerasimenko
© G. Wattieaux et al. 2020
Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.