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Sunspot Magnetic Fields and High Energy Electrons in Flares

Published online by Cambridge University Press:  14 August 2015

Tatsuo Takakura
Tatsuo Takakura*
Affiliation:
Tokyo Astronomical Observatory, University of Tokyo, Mitaka, Tokyo, Japan

Abstract

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A balloon observation of an impulsive hard X-ray burst on September 27, 1969 showed the size of the source to be one arc minute or less. It was remarkably smaller than the associated Hα flare with a size of 3 arc min.

The efficient acceleration of electrons and the trigger of the flares are suggested to be attributed to a large scale electric potential field caused by a gas motion near the photosphere. The primary cause of the onset of flares would be the acceleration of electrons. The electrons excite plasma waves which make the conductivity lower by several orders, so that the electromagnetic energy I2L stored before the onset of the flare would be suddenly converted into the heat due to the ohmic loss.

Type
Part IV: Observations of Magnetic Fields Associated with Flares and Other Transitory Phenomena
Information
Symposium - International Astronomical Union , Volume 43: Solar Magnetic Fields , 1971 , pp. 390 - 396
Copyright
Copyright © Reidel 1971 

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