Some Studies on Sunspots in relation to H_ɑ-Flares & Radiobursts

Abstract

A statistical investigation has been done on the active regions in relation to flares and radiobursts produced by them. Important results obtained are as follows. (i)The sunspots of larger area generally have complex and delta configurations and have magnetic fields of higher values. (ii)The flare activity increases with the increase of magnetic field for all configurations of sunspots and is highest for delta types for field up to 2500 gauss and, for complex types, in the field range 2500-3000 gauss. (iii) The sunspot bursts' association is highest for delta types and lowest for unipolar types of sunspots in all the observing frequencies under consideration and is higher in greater magnetic fields. (iv) The flare and burst activities are higher in case of changing type of configuration and also during the growing stage of sunspots.