Simultaneous VLA observations of a flare at 6 and 20 centimeter wavelengths

Using the Very Large Array at 6 and 20 cm wavelengths, a May 15, 1980 solar flare was mapped. The 1B flare, as observed in H alpha at Mees Solar Observatory, Maui, Hawaii, appeared as two sequential flares occurring at different neutral lines. The peaks of the time profile at 20 cm were delayed with respect to the 6 cm counterparts, but they were related to each other and to the H alpha activity. At 20 cm, precursor activity occurred, and an oppositely polarized source an arcminute away from the main burst may have triggered the flare. The main 20 cm emission appeared to be displaced limbward from the 6 cm burst. If both the 6 and 20 cm emission originated in the same system of loops, it is inferred that the apparent lateral displacement was caused by a height difference of 33,000 km in the sources of emission.