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Periodic Acceleration of Electrons in the 1998 November 10 Solar Flare

A. Asai·M. Shimojo·H. Isobe·T. Morimoto·T. Yokoyama·K. Shibasaki·H. Nakajima
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Abstract

We present an examination of the multi-wavelength observation of a C7.9 flare which occurred on 1998 November 10. This is the first time of imaging observation of the quasi-periodic pulsations (QPPs). Four bursts were observed with the hard X-ray telescope aboard Yohkoh and the Nobeyama Radioheliograph during the impulsive phase of the flare. In the second burst, the hard X-ray and microwave time profiles clearly showed a QPP. We estimated the Alfven transit time along the flare loop using the images of the soft X-ray telescope aboard it Yohkoh and the photospheric magnetgrams, and found that the transit time was almost equal to the period of the QPP. We therefore suggest, based on a shock acceleration model, that variations of macroscopic magnetic structures, such as oscillations of coronal loops, affect the efficiency of particle injection/acceleration.

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A. Asai, M. Shimojo, H. Isobe, T. Morimoto, T. Yokoyama, K. Shibasaki, H. Nakajima. 2001-11-01. Periodic Acceleration of Electrons in the 1998 November 10 Solar Flare. https://doi.org/10.1086/338052

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