Three-dimensional Features of the Outer Heliosphere Due to Coupling between the Interstellar and Heliospheric Magnetic Field. V. The Bow Wave, Heliospheric Boundary Layer, Instabilities, and Magnetic Reconnection
arXiv:1706.09637 · doi:10.3847/1538-4357/aa7d4f
Abstract
The heliosphere is formed due to interaction between the solar wind (SW) and local interstellar medium (LISM). The shape and position of the heliospheric boundary, the heliopause, in space depend on the parameters of interacting plasma flows. The interplay between the asymmetrizing effect of the interstellar magnetic field and charge exchange between ions and neutral atoms plays an important role in the SW-LISM interaction. By performing three-dimensional, MHD plasma / kinetic neutral atom simulations, we determine the width of the outer heliosheath - the LISM plasma region affected by the presence of the heliosphere - and analyze quantitatively the distributions in front of the heliopause. It is shown that charge exchange modifies the LISM plasma to such extent that the contribution of a shock transition to the total variation of plasma parameters becomes small even if the LISM velocity exceeds the fast magnetosonic speed in the unperturbed medium. By performing adaptive mesh refinement simulations, we show that a distinct boundary layer of decreased plasma density and enhanced magnetic field should be observed on the interstellar side of the heliopause. We show that this behavior is in agreement with the plasma oscillations of increasing frequency observed by the plasma wave instrument onboard Voyager 1. We also demonstrate that Voyager observations in the inner heliosheath between the heliospheric termination shock and the heliopause are consistent with dissipation of the heliospheric magnetic field. The choice of LISM parameters in this analysis is based on the simulations that fit observations of energetic neutral atoms performed by IBEX.
Accepted for publication in Astrophysical Journal
References in corpus (13)
- Instability of current sheets and formation of plasmoid chains
- Numerical Tests of Fast Reconnection in Weakly Stochastic Magnetic Fields
- Probing Heliospheric Asymmetries with an MHD-kinetic Model
- Comparing various multi-component global heliosphere models
- Spatial Confinement of the IBEX Ribbon: A Dominant Turbulence Mechanism
- Neutral H density at the termination shock: a consolidation of recent results
- Modeling Shocks Detected by Voyager 1 in the Local Interstellar Medium
- Modeling the Solar Wind at the Ulysses, Voyager, and New Horizons Spacecraft
- The effect of reconnection on the structure of the Sun's open-closed-flux boundary
- Pickup Ion Effect of the Solar Wind Interaction with the Local Interstellar Medium
- The formation of magnetic depletions and flux annihilation due to reconnection in the heliosheath
- Seven New Carbon-Enhanced Metal-Poor RR Lyrae Stars
- Connecting the interstellar magnetic field at the heliosphere to the Loop I superbubble