Abstract

We analyze the pre-flare and impulsive phase of an eruptive (two-ribbon) flare at several wavelengths. The total energy (mechanical plus radiative) released by the flare is 8 x 1030 erg, about a factor 6 higher than the free magnetic energy (1.3 1030 erg) estimated from the non-potentiality of the magnetic field configuration in the flare area. During the impulsive phase, we find a very good time coincidence between the hard X-ray light curve and the light curves for 2 small areas (≃ 4″ in size) in the red wing of the Hα line and in the He-D3 line center. This temporal coincidence is compatible with the interpretation that hard X-ray emission is produced by bremsstrahlung of accelerated electron beams striking these dense areas. For the other regions of the Hα ribbons we find more gradual light curves, suggesting a different energy transport mechanism such as conduction.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call