Magnetic fields in the outer heliosheath, particle trapping, and a promising direction to explore with the Interstellar Probe
Abstract
We re-examines the geometry of interstellar magnetic field lines close to the boundary of the heliosphere as a particular case of an interaction between a uniform magnetized flow of plasma and a blunt obstacle representing the heliopause. The choice of an analytic model allows us to qualitatively study the resulting magnetic field draping pattern while avoiding unphysical dissipation across the heliopause inherent in numerical MHD models. We focus our attention on the region in the direction of the unperturbed LISM field (the IBEX ribbon center), where the field lines are spread apart by the surface of the heliopause. Such field parting establishes a region of weaker magnetic field of about 100 au in size that acts as a giant magnetic trap affecting the propagation of energetic charged particles such as galactic cosmic rays. We find that absorption of cosmic rays by the heliopause could lead to a development of a field-aligned anisotropy in the outward direction. We also show that the region around the magnetic trap is the preferred location for cosmic rays entry into the heliosphere. Exploring this region with the Interstellar Probe could lead to qualitatively new science compared with the regions already explored by the Voyagers.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMSH019..06F
- Keywords:
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- 2124 Heliopause and solar wind termination;
- INTERPLANETARY PHYSICS;
- 2126 Heliosphere/interstellar medium interactions;
- INTERPLANETARY PHYSICS;
- 2129 Interplanetary dust;
- INTERPLANETARY PHYSICS;
- 6224 Kuiper belt objects;
- PLANETARY SCIENCES: SOLAR SYSTEM OBJECTS