RECONNECTION-DRIVEN DYNAMICS OF CORONAL-HOLE BOUNDARIES

Journal Article · Sun Dec 20 00:00:00 EST 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/707/2/1427· OSTI ID:21392559

Edmondson, J K; Antiochos, S K ^[1]; Lynch, B J ^[2]; DeVore, C R ^[3]

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1. NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
2. Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States)
3. Naval Research Laboratory, Washington, DC 20375 (United States)

We investigate the effect of magnetic reconnection on the boundary between open and closed magnetic field in the solar corona. The magnetic topology for our numerical study consists of a global dipole that gives rise to polar coronal holes and an equatorial streamer belt, and a smaller active-region bipole embedded inside the closed-field streamer belt. The initially potential magnetic field is energized by a rotational motion at the photosphere that slowly twists the embedded-bipole flux. Due to the applied stress, the bipole field expands outward and reconnects with the surrounding closed flux, eventually tunneling through the streamer boundary and encountering the open flux of the coronal hole. The resulting interchange reconnection between closed and open field releases the magnetic twist and free energy trapped inside the bipole onto open field lines, where they freely escape into the heliosphere along with the entrained closed-field plasma. Thereafter, the bipole field relaxes and reconnects back down into the interior of the streamer belt. Our simulation shows that the detailed properties of magnetic reconnection can be crucial to the coronal magnetic topology, which implies that both potential-field source-surface and quasi-steady magnetohydrodynamic models may often be an inadequate description of the corona and solar wind. We discuss the implications of our results for understanding the dynamics of the boundary between open and closed field on the Sun and the origins of the slow wind.

• OSTI ID: 21392559
• Journal Information: Astrophysical Journal, Vol. 707, Issue 2; Other Information: DOI: 10.1088/0004-637X/707/2/1427; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
DIPOLES
FREE ENERGY
HELIOSPHERE
MAGNETIC FIELDS
MAGNETIC RECONNECTION
MAGNETOHYDRODYNAMICS
NUMERICAL ANALYSIS
PHOTOSPHERE
SIMULATION
SOLAR CORONA
SOLAR WIND
SUN
TOPOLOGY
TUNNEL EFFECT
ATMOSPHERES
ENERGY
FLUID MECHANICS
HYDRODYNAMICS
MAIN SEQUENCE STARS
MATHEMATICS
MECHANICS
MULTIPOLES
PHYSICAL PROPERTIES
SOLAR ACTIVITY
SOLAR ATMOSPHERE
STARS
STELLAR ACTIVITY
STELLAR ATMOSPHERES
STELLAR CORONAE
STELLAR WINDS
THERMODYNAMIC PROPERTIES