Dependence of radio emission in large H? flares 1967?1970 upon the orientation of the local solar magnetic field

Abstract

During 1967During -1970, the greatness of ~ 90 large flares (Ha importance > 2) was influenced by the orientation of the large-scale (~ 100000 km) magnetic field structure over the flare site. Although the average X-ray and optical emissions are only slightly larger for flares with their overlying fields directed southward, as opposed to northward, the meter-wave-length prompt flux maxima are, on average, an order of magnitude greater for the flares with southward oriented magnetic fields. There is a comparable, but possibly smaller difference in the 10 cm-2 fluxes. We therefore conclude that, during this period, the orientation of the overlying magnetic field affects the amount of electromagnetic flare energy radiated promptly in the corona (10 cm-2 and m-2), relative to that radiated in the chromosphere (X-ray and optical). We demonstrate that this statistical effect shows some variability in degree during the period, although the trend is consistent throughout.

Chromospheric Flares and 210 MHz Radio Emission

“…The relationship of radio bursts and solar flares has been pointed out [1][2][3]. Dodson [4] and Dodson and Hedeman [5][6] discovered that flares coincide with or precede radio storms at 200 MHz (150 cm).…”