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arXiv · 1702.01905

Can the temperature of Ellerman Bombs be more than 10000K?

C. Fang·Q. Hao·M. D. Ding·Z. Li
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Abstract

Ellerman bombs (EBs) are small brightening events in the solar lower atmosphere. By original definition, the main EB's characteristic is the two emission bumps in both wings of chromospheric lines, such as H$α$ and Ca II 8542 Å lines. Up to now, most authors found that the temperature increase of EBs around the temperature minimum region is in the range of 600K-3000K. However, with recent IRIS observations, some authors proposed that the temperature increase of EBs could be more than 10000K. Using non-LTE semi-empirical modeling, we investigate the line profiles, continuum emission and the radiative losses for the EB models with different temperature increases, and compare them with observations. Our result indicates that if the EB maximum temperature attains more than 10000K around the temperature minimum region, then the resulted H$α$ and Ca II 8542 Å line profiles and the continuum emission would be much stronger than that of EB observations. Moreover, due to the high radiative losses, the high temperature EB would have a very short lifetime, which is not comparable with the observations. Thus, our study does not support the proposal that the EB temperatures are higher than 10000K.

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C. Fang, Q. Hao, M. D. Ding, Z. Li. 2017-02-07. Can the temperature of Ellerman Bombs be more than 10000K?. https://doi.org/10.1088/1674-4527%2F17%2F4%2F31

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