Multi-ion Multi-fluid Simulations of the Effects of Pick-up Ions on the Global Structure of the Heliosphere
Abstract
We present the first 3D MHD multi-ion, multi-fluid simulations including pick-up ions as a separate fluid on the global structure of the heliosphere. Pick-up ions, formed by charge exchange between the solar wind and local interstellar medium, are thought to account for the missing thermal energy measured by Voyager 2 at the crossing of the Termination Shock. By treating the pick-up ions as a separate fluid (with an isotropic distribution) from the solar wind thermal plasma, we are able to isolate the properties of the suprathermal pick-up ion plasma from that of the thermal solar wind. In addition to the two charged ion fluids, we include four neutral fluids which interact via charge exchange with the pick-up ion plasma. We show that pick-up ions are dynamically important in the outer heliosphere, thinning and heating the heliosheath. Since the neutral fluids are imprinted with the properties of the plasma they are born from, this work has implications for the Energetic Neutral Atom (ENA) maps of the global heliosphere. We discuss briefly the effects on the global ENA maps of the heliosphere in addition to measurements along the Voyager 1 and 2 trajectories.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2016
- Bibcode:
- 2016AGUFMSH41C2543B
- Keywords:
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- 2104 Cosmic rays;
- INTERPLANETARY PHYSICSDE: 2124 Heliopause and solar wind termination;
- INTERPLANETARY PHYSICSDE: 2126 Heliosphere/interstellar medium interactions;
- INTERPLANETARY PHYSICSDE: 7835 Magnetic reconnection;
- SPACE PLASMA PHYSICS