SDO/AIA OBSERVATION OF KELVIN-HELMHOLTZ INSTABILITY IN THE SOLAR CORONA

Journal Article · Fri Jun 10 00:00:00 EDT 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/734/1/L11· OSTI ID:21562612

Ofman, L ^[1]; Thompson, B J ^[2]

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1. Department of Physics, Catholic University of America, Washington, DC 20064 (United States)
2. NASA Goddard Space Flight Center, Code 671, Greenbelt, MD 20771 (United States)

We present observations of the formation, propagation, and decay of vortex-shaped features in coronal images from the Solar Dynamics Observatory associated with an eruption starting at about 2:30 UT on 2010 April 8. The series of vortices were formed along the interface between an erupting (dimming) region and the surrounding corona. They ranged in size from several to 10 arcsec and traveled along the interface at 6-14 km s{sup -1}. The features were clearly visible in six out of the seven different EUV wave bands of the Atmospheric Imaging Assembly. Based on the structure, formation, propagation, and decay of these features, we identified the event as the first observation of the Kelvin-Helmholtz instability (KHI) in the corona in EUV. The interpretation is supported by linear analysis and by a nonlinear 2.5-dimensional magnetohydrodynamic model of KHI. We conclude that the instability is driven by the velocity shear between the erupting and closed magnetic field of the coronal mass ejection. The shear-flow-driven instability can play an important role in energy transfer processes in coronal plasma.

• OSTI ID: 21562612
• Journal Information: Astrophysical Journal Letters, Vol. 734, Issue 1; Other Information: DOI: 10.1088/2041-8205/734/1/L11; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ENERGY TRANSFER
ERUPTION
EXTREME ULTRAVIOLET RADIATION
HELMHOLTZ INSTABILITY
MAGNETIC FIELDS
MASS
SHEAR
SOLAR CORONA
VORTICES
ATMOSPHERES
ELECTROMAGNETIC RADIATION
INSTABILITY
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
RADIATIONS
SOLAR ATMOSPHERE
STELLAR ATMOSPHERES
STELLAR CORONAE
ULTRAVIOLET RADIATION