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arXiv · 1107.1905

Center-to-Limb Variation of Radio Emissions from Thermal-Rich and Thermal-Poor Solar Flares

Tomoko Kawate·Ayumi Asai·Ichimoto Kiyoshi
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Abstract

A statistical analysis of radio flare events was performed by using the event list of Nobeyama Radioheliograph in 1996-2009. We examined center-to-limb variations of 17GHz and 34GHz flux by dividing the flare events into different groups with respect to the 'thermal plasma richness' (ratio of the peak flux of soft X-ray to non-thermal radio emissions) and the duration of radio bursts. It is found that peak flux of 17 and 34GHz tend to be higher toward the limb for thermal-rich flares with short durations. We propose that the thermal-rich flares, which are supposed to be associated with an efficient precipitation of high energy particles into the chromosphere, have a pitch angle distribution of non-thermal electrons with a higher population along the flare loop.

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Tomoko Kawate, Ayumi Asai, Ichimoto Kiyoshi. 2011-07-10. Center-to-Limb Variation of Radio Emissions from Thermal-Rich and Thermal-Poor Solar Flares. https://doi.org/10.1093/pasj%2F63.6.1251

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