Severny's theory has not emerged as fuli proof in magnetic field
high gradient of fields. In fact, substantial modifications in the magnetic field structure are actually observed in the flare region after the flare has died out. Moreover, large magnetic field gradient is capable of accelerating particles to high energies which can subsequently emit radiation in wavelengths ranging from X-rays to long radio waves, as are actually observed in flares. But there are other observations of magnetic fields which Severny's cannot explain, and so Severny's theory has not emerged as fuli proof.
A plausible theory of the origin of flares has also been proposed by Gold and Hoyle. Their theory relies for the energy source on coalescing and cancellation of two bundles of twisted magnetic lines of force. They imagine a filament consisting of a bundle of lines of force which emerges from a point in the photosphere and re-enters ät another point thus forming an arch.
This bunch of lines of force may be twisted due to highly In order that this energy may be released abruptly, a pair of such fil ments with initial magnetic fields in opposite directions but the same sense of twisting is hypothesized. Two such filaments placed close to each other will attract each other, interpenetrate, and a part of the field will be annihilated in a time-scale of the order of 10 seconds.convective motion in the subphotospheric layer.
The energy density of this convective mass motion is 10 erg em only a few per cent of which is associated with flarë phenomena. The twisting of the field can greatly increase the intensit, of the initial moderate field. Calculation shows that an amount of magnetic energy equal to - 100 filament. This is the right amount of energy that is involved with flare phenomena.
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