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Title: Transient shocks beyond the heliopause

Abstract

The heliopause is a rich, dynamic surface affected by the time-dependent solar wind. Stream interactions due to coronal mass ejections (CMEs), corotating interaction regions (CIRs), and other transient phenomena are known to merge producing global merged interaction regions (GMIRs). Numerical simulations of the solar wind interaction with the local interstellar medium (LISM) show that GMIRs, as well other time-dependent structures in the solar wind, may produce compression/rarefaction waves and shocks in the LISM behind the heliopause. These shocks may initiate wave activity observed by the Voyager spacecraft. The magnetometer onboard Voyager 1 indeed observed a few structures that may be interpreted as shocks. We present numerical simulations of such shocks in the year of 2000, when both Voyager spacecraft were in the supersonic solar wind region, and in 2012, when Voyager 1 observed traveling shocks. In the former case, Voyager observations themselves provide time- dependent boundary conditions in the solar wind. In the latter case, we use OMNI data at 1 AU to analyze the plasma and magnetic field behavior after Voyager 1 crossed the heliospheric boundary. Numerical results are compared with spacecraft observations.

Authors:
 [1];  [1];  [2]
  1. Univ. of Alabama, Huntsville, AL (United States). Department of Space Science and Center for Space Plasma and Aeronomic Research
  2. NASA Goddard Space Flight Center (GSFC), Greenbelt, MD (United States)
Publication Date:
Research Org.:
Univ. of Alabama, Huntsville, AL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24); National Aeronautic and Space Administration (NASA); National Science Foundation (NSF)
OSTI Identifier:
1326076
Grant/Contract Number:
SC0008334; NNX12AB30G; NNX14AJ41G; NNX14AJ53G; OCI-1144120; SMD-13-4187
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Journal of Physics. Conference Series
Additional Journal Information:
Journal Volume: 642; Journal ID: ISSN 1742-6588
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Fermo, R. L., Pogorelov, N. V., and Burlaga, L. F.. Transient shocks beyond the heliopause. United States: N. p., 2015. Web. doi:10.1088/1742-6596/642/1/012008.
Fermo, R. L., Pogorelov, N. V., & Burlaga, L. F.. Transient shocks beyond the heliopause. United States. doi:10.1088/1742-6596/642/1/012008.
Fermo, R. L., Pogorelov, N. V., and Burlaga, L. F.. Wed . "Transient shocks beyond the heliopause". United States. doi:10.1088/1742-6596/642/1/012008. https://www.osti.gov/servlets/purl/1326076.
@article{osti_1326076,
title = {Transient shocks beyond the heliopause},
author = {Fermo, R. L. and Pogorelov, N. V. and Burlaga, L. F.},
abstractNote = {The heliopause is a rich, dynamic surface affected by the time-dependent solar wind. Stream interactions due to coronal mass ejections (CMEs), corotating interaction regions (CIRs), and other transient phenomena are known to merge producing global merged interaction regions (GMIRs). Numerical simulations of the solar wind interaction with the local interstellar medium (LISM) show that GMIRs, as well other time-dependent structures in the solar wind, may produce compression/rarefaction waves and shocks in the LISM behind the heliopause. These shocks may initiate wave activity observed by the Voyager spacecraft. The magnetometer onboard Voyager 1 indeed observed a few structures that may be interpreted as shocks. We present numerical simulations of such shocks in the year of 2000, when both Voyager spacecraft were in the supersonic solar wind region, and in 2012, when Voyager 1 observed traveling shocks. In the former case, Voyager observations themselves provide time- dependent boundary conditions in the solar wind. In the latter case, we use OMNI data at 1 AU to analyze the plasma and magnetic field behavior after Voyager 1 crossed the heliospheric boundary. Numerical results are compared with spacecraft observations.},
doi = {10.1088/1742-6596/642/1/012008},
journal = {Journal of Physics. Conference Series},
number = ,
volume = 642,
place = {United States},
year = {Wed Sep 30 00:00:00 EDT 2015},
month = {Wed Sep 30 00:00:00 EDT 2015}
}

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