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arXiv · 0910.4245

A Technique for Automated Determination of Flare-ribbon Separation and Energy Release

R. A. Maurya·A. Ambastha
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Abstract

We present a technique for automatic determination of flare-ribbon separation and the energy released during the course of two-ribbon flares. We have used chromospheric H$α$ filtergrams and photospheric line-of-sight magnetograms to analyse flare-ribbon separation and magnetic-field structures, respectively. Flare-ribbons were first enhanced and then extracted by the technique of "region growing", i.e., a morphological operator to help resolve the flare-ribbons. Separation of flare-ribbons was then estimated from magnetic polarity reversal line using an automatic technique implemented into Interactive Data Language (IDL\tm) platform. Finally, the rate of flare-energy release was calculated using photospheric magnetic-field data and the corresponding separation of the chromospheric H$α$ flare-ribbons. This method could be applied to measure the motion of any feature of interest (e.g., intensity, magnetic, Doppler) from a given point of reference.

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R. A. Maurya, A. Ambastha. 2009-10-22. A Technique for Automated Determination of Flare-ribbon Separation and Energy Release. https://doi.org/10.1007/s11207-009-9488-5

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