The Role of Pickup Ions in Global Simulations of the Heliosphere
Abstract
The interaction of the solar wind (SW) with the partially ionized local interstellar medium (LISM) is affected by charge exchange between ions and neutral atoms. Charge exchange also produces pick up ions (PUIs), which are known to carry most of the thermal energy of plasma in the outer heliosphere. Treating interstellar PUIs as a separate population of plasma is important because this allows one to describe correctly the physical processes affecting their evolution and, especially, their crossing of the heliospheric termination shock. We present the results of our global MHD simulations of the heliosphere, which take into account PUIs as a separate fluid. We validate these simulations by comparing them to observational data from the Voyager spacecraft. In addition, we show the results of our data analysis of Ulysses Solar Wind Ion Composition Spectrometer (SWICS) measurements, which allowed us to derive the distribution of PUI density and temperature along some segments of the spacecraft trajectory. This work makes it possible to describe the SW-LISM interaction with higher accuracy and gives us a better understanding of the outer heliosphere and heliospheric interface.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMSH0230011R
- Keywords:
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- 2114 Energetic particles;
- INTERPLANETARY PHYSICS;
- 2124 Heliopause and solar wind termination;
- INTERPLANETARY PHYSICS;
- 2126 Heliosphere/interstellar medium interactions;
- INTERPLANETARY PHYSICS;
- 2151 Neutral particles;
- INTERPLANETARY PHYSICS