Abstract
We obtained a set of well-observed 2D Hα spectral data of a 1N/M1.5 flare from the Solar Tower of Nanjing University. Using the Hα spectra, the sites of electron precipitation and high coronal pressure have been found, and the Doppler velocity was calculated from the red asymmetry of the Hα emission line by use of the bisector method. The current density distribution was also computed from magnetic field measurements. We have coaligned the Hα spectroheliograms and the magnetograms. It was found that the sites of electron precipitation were at the edge of a main current area. The sites of red asymmetry coincided with those of high coronal pressure. The flare reached its maximum in the magnetic shear region, though it began in a weak magnetic field. Several flare models are discussed to see which one could satisfy the observation.
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Zhao, J., Fang, C. & De Ding, M. ANALYSIS OF 2D Hα SPECTRA AND MAGNETIC FIELD DURING THE IMPULSIVE PHASE OF A SOLAR FLARE. Solar Physics 173, 121–130 (1997). https://doi.org/10.1023/A:1004919206804
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DOI: https://doi.org/10.1023/A:1004919206804