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arXiv · 1805.05587

Mass loading at 67P/Churyumov-Gerasimenko: a case study

E. Behar·H. Nilsson·G. Stenberg Wieser·Z. Nemeth·T. W. Broiles·I. Richter
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Abstract

We study the dynamics of the interaction between the solar wind ions and a partially ionized atmosphere around a comet, at a distance of 2.88 AU from the sun during a period of low nucleus activity. Comparing particle data and mag- netic field data for a case study, we highlight the prime role of the solar wind electric field in the cometary ion dynamics. Cometary ion and solar wind proton flow directions evolve in a correlated manner, as expected from the theory of mass loading. We find that the main component of the acceler- ated cometary ion flow direction is along the anti-sunward direction, and not along the convective electric field direc- tion. This is interpreted as the effect of an anti-sunward polarisation electric field adding up to the solar wind con- vective electric field.

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E. Behar, H. Nilsson, G. Stenberg Wieser, Z. Nemeth, T. W. Broiles, I. Richter. 2018-05-15. Mass loading at 67P/Churyumov-Gerasimenko: a case study. https://doi.org/10.1002/2015gl067436

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