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arXiv · 1210.2916

X-ray and UV investigation into the magnetic connectivity of a solar flare

Hamish A. S. Reid·Nicole Vilmer·Guillaume Aulanier·Etienne Pariat
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Abstract

We investigate the X-ray and UV emission detected by RHESSI and TRACE in the context of a solar flare on the 16th November 2002 with the goal of better understanding the evolution of the flare. We analysed the characteristics of the X-ray emission in the 12-25 and 25-50 keV energy range while we looked at the UV emission at 1600 Å. The flare appears to have two distinct phases of emission separated by a 25-second time delay, with the first phase being energetically more important. We found good temporal and spatial agreement between the 25-50 keV X-rays and the most intense areas of the 1600 Å UV emission. We also observed an extended 100-arcsecond < 25 keV source that appears coronal in nature and connects two separated UV ribbons later in the flare. Using the observational properties in X-ray and UV wavelengths, we propose two explanations for the flare evolution in relation to the spine/fan magnetic field topology and the accelerated electrons. We find that a combination of quasi separatrix layer reconnection and null-point reconnection is required to account for the observed properties of the X-ray and UV emission.

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Hamish A. S. Reid, Nicole Vilmer, Guillaume Aulanier, Etienne Pariat. 2012-10-10. X-ray and UV investigation into the magnetic connectivity of a solar flare. https://doi.org/10.1051/0004-6361%2F201219562

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