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Title: A POROUS, LAYERED HELIOPAUSE

Abstract

The picture of the heliopause (HP)-the boundary between the domains of the Sun and the local interstellar medium (LISM)-as a pristine interface with a large rotation in the magnetic field fails to describe recent Voyager 1 (V1) data. Magnetohydrodynamic (MHD) simulations of the global heliosphere reveal that the rotation angle of the magnetic field across the HP at V1 is small. Particle-in-cell simulations, based on cuts through the MHD model at V1's location, suggest that the sectored region of the heliosheath (HS) produces large-scale magnetic islands that reconnect with the interstellar magnetic field while mixing LISM and HS plasma. Cuts across the simulation reveal multiple, anti-correlated jumps in the number densities of LISM and HS particles, similar to those observed, at the magnetic separatrices. A model is presented, based on both the observations and simulations, of the HP as a porous, multi-layered structure threaded by magnetic fields. This model further suggests that contrary to the conclusions of recent papers, V1 has already crossed the HP.

Authors:
;  [1];  [2]
  1. Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 (United States)
  2. Department of Astronomy, Boston University, 725 Commonwealth Avenue, Boston, MA 02215 (United States)
Publication Date:
OSTI Identifier:
22136546
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 774; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; DENSITY; HELIOSPHERE; INTERSTELLAR MAGNETIC FIELDS; MAGNETIC ISLANDS; MAGNETOHYDRODYNAMICS; PLASMA SIMULATION; ROTATION; SUN; VOYAGER SPACE PROBES

Citation Formats

Swisdak, M., Drake, J. F., and Opher, M., E-mail: swisdak@umd.edu, E-mail: drake@umd.edu, E-mail: mopher@bu.edu. A POROUS, LAYERED HELIOPAUSE. United States: N. p., 2013. Web. doi:10.1088/2041-8205/774/1/L8.
Swisdak, M., Drake, J. F., & Opher, M., E-mail: swisdak@umd.edu, E-mail: drake@umd.edu, E-mail: mopher@bu.edu. A POROUS, LAYERED HELIOPAUSE. United States. doi:10.1088/2041-8205/774/1/L8.
Swisdak, M., Drake, J. F., and Opher, M., E-mail: swisdak@umd.edu, E-mail: drake@umd.edu, E-mail: mopher@bu.edu. 2013. "A POROUS, LAYERED HELIOPAUSE". United States. doi:10.1088/2041-8205/774/1/L8.
@article{osti_22136546,
title = {A POROUS, LAYERED HELIOPAUSE},
author = {Swisdak, M. and Drake, J. F. and Opher, M., E-mail: swisdak@umd.edu, E-mail: drake@umd.edu, E-mail: mopher@bu.edu},
abstractNote = {The picture of the heliopause (HP)-the boundary between the domains of the Sun and the local interstellar medium (LISM)-as a pristine interface with a large rotation in the magnetic field fails to describe recent Voyager 1 (V1) data. Magnetohydrodynamic (MHD) simulations of the global heliosphere reveal that the rotation angle of the magnetic field across the HP at V1 is small. Particle-in-cell simulations, based on cuts through the MHD model at V1's location, suggest that the sectored region of the heliosheath (HS) produces large-scale magnetic islands that reconnect with the interstellar magnetic field while mixing LISM and HS plasma. Cuts across the simulation reveal multiple, anti-correlated jumps in the number densities of LISM and HS particles, similar to those observed, at the magnetic separatrices. A model is presented, based on both the observations and simulations, of the HP as a porous, multi-layered structure threaded by magnetic fields. This model further suggests that contrary to the conclusions of recent papers, V1 has already crossed the HP.},
doi = {10.1088/2041-8205/774/1/L8},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 774,
place = {United States},
year = 2013,
month = 9
}
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