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arXiv · 1212.1361

Can Superflares Occur on Our Sun?

Kazunari Shibata·Hiroaki Isobe·Andrew Hillier·Arnab Rai Choudhuri·Hiroyuki Maehara·Takako T. Ishii·Takuya Shibayama·Shota Notsu·Yuta Notsu·Takashi Nagao·Satoshi Honda·Daisaku Nogami
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Abstract

Recent observations of solar type stars with the Kepler satellite by Maehara et al. have revealed the existence of superflares (with energy of 10^33 - 10^35 erg) on Sun-like stars, which are similar to our Sun in their surface temperature (5600 K - 6000 K) and slow rotation (rotational period > 10 days). From the statistical analysis of these superflares, it was found that superflares with energy 10^34 erg occur once in 800 years and superflares with 10^35 erg occur once in 5000 years on Sun-like stars. In this paper, we examine whether superflares with energy of 10^33 - 10^35 erg could occur on the present Sun through the use of simple order-of-magnitude estimates based on current ideas relating to the mechanisms of the solar dynamo.

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Kazunari Shibata, Hiroaki Isobe, Andrew Hillier, Arnab Rai Choudhuri, Hiroyuki Maehara, Takako T. Ishii, Takuya Shibayama, Shota Notsu, Yuta Notsu, Takashi Nagao, Satoshi Honda, Daisaku Nogami. 2012-12-06. Can Superflares Occur on Our Sun?. https://doi.org/10.1093/pasj%2F65.3.49

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