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Title: Formation of Heliospheric Arcs of Slow Solar Wind

Abstract

A major challenge in solar and heliospheric physics is understanding the origin and nature of the so-called slow solar wind. The Sun’s atmosphere is divided into magnetically open regions, known as coronal holes, where the plasma streams out freely and fills the solar system, and closed regions, where the plasma is confined to coronal loops. The boundary between these regions extends outward as the heliospheric current sheet (HCS). Measurements of plasma composition strongly imply that much of the slow wind consists of plasma from the closed corona that escapes onto open field lines, presumably by field-line opening or by interchange reconnection. Both of these processes are expected to release closed-field plasma into the solar wind within and immediately adjacent to the HCS. Mysteriously, however, slow wind with closed-field plasma composition is often observed in situ far from the HCS. We use high-resolution, three-dimensional, magnetohydrodynamic simulations to calculate the dynamics of a coronal hole with a geometry that includes a narrow corridor flanked by closed field and is driven by supergranule-like flows at the coronal-hole boundary. These dynamics produce giant arcs of closed-field plasma that originate at the open-closed boundary in the corona, but extend far from the HCS and spanmore » tens of degrees in latitude and longitude at Earth. We conclude that such structures can account for the long-puzzling slow-wind observations.« less

Authors:
;  [1]; ;  [2];  [3]
  1. Department of Climate and Space Sciences and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)
  2. Heliophysics Science Division, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
  3. Department of Mathematical Sciences, Durham University, Durham DH1 3LE (United Kingdom)
Publication Date:
OSTI Identifier:
22654484
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 840; 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; ATMOSPHERES; HOLES; MAGNETIC FIELDS; MAGNETIC RECONNECTION; MAGNETOHYDRODYNAMICS; PLASMA; RESOLUTION; SIMULATION; SOLAR SYSTEM; SOLAR WIND; STREAMS; SUN; THREE-DIMENSIONAL CALCULATIONS

Citation Formats

Higginson, A. K., Zurbuchen, T. H., Antiochos, S. K., DeVore, C. R., and Wyper, P. F., E-mail: aleida@umich.edu. Formation of Heliospheric Arcs of Slow Solar Wind. United States: N. p., 2017. Web. doi:10.3847/2041-8213/AA6D72.
Higginson, A. K., Zurbuchen, T. H., Antiochos, S. K., DeVore, C. R., & Wyper, P. F., E-mail: aleida@umich.edu. Formation of Heliospheric Arcs of Slow Solar Wind. United States. doi:10.3847/2041-8213/AA6D72.
Higginson, A. K., Zurbuchen, T. H., Antiochos, S. K., DeVore, C. R., and Wyper, P. F., E-mail: aleida@umich.edu. Mon . "Formation of Heliospheric Arcs of Slow Solar Wind". United States. doi:10.3847/2041-8213/AA6D72.
@article{osti_22654484,
title = {Formation of Heliospheric Arcs of Slow Solar Wind},
author = {Higginson, A. K. and Zurbuchen, T. H. and Antiochos, S. K. and DeVore, C. R. and Wyper, P. F., E-mail: aleida@umich.edu},
abstractNote = {A major challenge in solar and heliospheric physics is understanding the origin and nature of the so-called slow solar wind. The Sun’s atmosphere is divided into magnetically open regions, known as coronal holes, where the plasma streams out freely and fills the solar system, and closed regions, where the plasma is confined to coronal loops. The boundary between these regions extends outward as the heliospheric current sheet (HCS). Measurements of plasma composition strongly imply that much of the slow wind consists of plasma from the closed corona that escapes onto open field lines, presumably by field-line opening or by interchange reconnection. Both of these processes are expected to release closed-field plasma into the solar wind within and immediately adjacent to the HCS. Mysteriously, however, slow wind with closed-field plasma composition is often observed in situ far from the HCS. We use high-resolution, three-dimensional, magnetohydrodynamic simulations to calculate the dynamics of a coronal hole with a geometry that includes a narrow corridor flanked by closed field and is driven by supergranule-like flows at the coronal-hole boundary. These dynamics produce giant arcs of closed-field plasma that originate at the open-closed boundary in the corona, but extend far from the HCS and span tens of degrees in latitude and longitude at Earth. We conclude that such structures can account for the long-puzzling slow-wind observations.},
doi = {10.3847/2041-8213/AA6D72},
journal = {Astrophysical Journal Letters},
number = 1,
volume = 840,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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