Coronal Cavities from SDO Observations
Abstract
Coronal cavities are circular darkened regions observed above the solar limb in white light and EUV coronal images. It is a region of low density relative to the surrounding corona. In this study, we are using synoptic maps made from EUV images from the Atmospheric Imager Assembly (AIA) instrument on the SDO to determine the structure and evolution of cavities. The synoptic maps, constructed from circular rings above the limb, are found to best show cavities in 211Å (Fe XIV, 2.0 MK) and 193 Å (Fe XII, 1.6 MK) pass bands. The high spatial and time resolution combined with the broad temperature coverage provides a consistent picture of the cavity material and the dynamics of the structure. Our goal is to study the cavity"s sizes (height, diameter and length), density and temperature properties. Moreover, we will examine the correlation between cavity morphology and underlying magnetic field distribution using Heliosesmic and Magnetic imager (HMI) instrument on SDO. This study will shed light on the origin, evolution and dynamics of coronal cavities.
- Publication:
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Solar Heliospheric and INterplanetary Environment (SHINE 2012)
- Pub Date:
- June 2012
- Bibcode:
- 2012shin.confE.207K