The Depiction of Coronal Structure in White-Light Images


Show simple item record Morgan, Huw Habbal, Shadia Rifai Woo, Richard 2007-10-04T15:28:17Z 2007-10-04T15:28:17Z 2006-07-01
dc.identifier.citation Morgan , H , Habbal , S R & Woo , R 2006 , ' The Depiction of Coronal Structure in White-Light Images ' Solar Physics , vol 236 , no. 2 , pp. 263-272 . , 10.1007/s11207-006-0113-6 en
dc.identifier.issn 0038-0938
dc.identifier.other PURE: 72528
dc.identifier.other dspace: 2160/337
dc.identifier.uri en
dc.description Morgan, Huw, Habbal, S.R., Woo, R., (2006) 'The Depiction of Coronal Structure in White-Light Images', Solar Physics 236(2) pp.263-272 RAE2008 en
dc.description.abstract The very steep decrease in density with heliocentric distance makes imaging of coronal density structures out to a few solar radii challenging. The radial gradient in brightness can be reduced using numerous image processing techniques, thus quantitative data are manipulated to provide qualitative images. We introduce a new normalizing-radial-graded filter (NRGF): a simple filter for removing the radial gradient to reveal coronal structure. Applied to polarized brightness observations of the corona, the NRGF produces images which are striking in their detail. Total-brightness, white-light images include contributions from the F corona, stray light, and other instrumental contributions which need to be removed as effectively as possible to properly reveal the electron corona structure. A new procedure for subtracting this background from LASCO C2 white-light, total-brightness images is introduced. The background is created from the unpolarized component of total-brightness images and is found to be remarkably time-invariant, remaining virtually unchanged over the solar cycle. By direct comparison with polarized-brightness data, we show that the new background-subtracting procedure is superior in depicting coronal structure accurately, particularly when used in conjunction with the NRGF. The effectiveness of the procedures is demonstrated on a series of LASCO C2 observations of a coronal mass ejection (CME). en
dc.format.extent 10 en
dc.language.iso eng
dc.relation.ispartof Solar Physics en
dc.title The Depiction of Coronal Structure in White-Light Images en
dc.type Text en
dc.type.publicationtype Article (Journal) en
dc.contributor.institution Institute of Mathematics & Physics (ADT) en
dc.contributor.institution Mathematics and Physics en
dc.description.status Peer reviewed en

Files in this item

This item appears in the following Collection(s)

Show simple item record

Search Cadair

Advanced Search


My Account