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Extraction of solar coronal magnetic loops with the directional 2D Morlet wavelet transform

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Biskri, S. [UCL] Antoine, Jean-Pierre [UCL] Inhester, B. Mekideche, F.

We present an automated extraction method based on the continuous wavelet transform (CWT) for analyzing solar magnetic loops. The aim of the work is to extract, from the images taken from solar EUV telescopes, the traces of bright loops presumably shaped by the magnetic field of the solar corona. The technique is that of wavelet analysis, using the two-dimensional Morlet wavelet, because of its efficiency in detecting oriented features, which allows us to follow closely the curvature of the loops. Next, we segment the wavelet modulus image and we threshold it, both globally and locally (i.e., adaptively), in order to eliminate the remaining noise. Altogether, our method performs well, it is robust and fast, and could be used as a standard tool for analyzing large data sets expected from missions like SDO.

Document type Article de périodique (Journal article) – Article de recherche
Access type Accès restreint
Publication date 2010
Language Anglais
Journal information "Solar Physics : a journal for solar and solar-stellar research and the study of solar terrestrial physics" - Vol. 262, no. 2, p. 373-385 (2010)
Peer reviewed yes
Publisher Springer (Dordrecht)
issn 0038-0938
e-issn 1573-093X
Publication status Publié
Affiliation UCL
Keywords Corona ; Magnetic loops ; Continuous wavelet transform ; Extraction ; Segmentation
Links
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Bibliographic reference Biskri, S. ; Antoine, Jean-Pierre ; Inhester, B. ; Mekideche, F.. Extraction of solar coronal magnetic loops with the directional 2D Morlet wavelet transform. In: Solar Physics : a journal for solar and solar-stellar research and the study of solar terrestrial physics, Vol. 262, no. 2, p. 373-385 (2010)
Permanent URL http://hdl.handle.net/2078.1/34009