The 3B/X3 solar flare of 27 February 1992

LÓPEZ FUENTES, M.C.; MANDRINI, C.H.; ROVIRA, M.G.; DÉMOULIN, P.

GEOFíSICA INTERNACIONAL

INST GEOPHYSICS UNAM

Año: 2000 vol. 39 p. 65 - 71

0016-7169

Active region NOAA 7070 was related to a 3B/X3 solar flare that occurred on February 27, 1992. The soft X-ray flareobservations were obtained by the SXT (Soft X-ray Telescope) on board the Yohkoh satellite, and those in Ha from the UdaipurObservatory. The location of the Ha kernels and ribbons, and the shape of soft X-ray loops are compared with the magnetic fieldmodel of the AR. Both, observations and model, suggest that the coronal loops are highly sheared before the flare and that theconfiguration relaxes after energy release. We compute the magnetic free energy at 2´1032 erg; this value is typical for the energyreleased by solar flares.