Hostname: page-component-8448b6f56d-mp689 Total loading time: 0 Render date: 2024-04-18T08:54:41.471Z Has data issue: false hasContentIssue false

Statistical properties of superflares on solar-type stars based on the Kepler 1-min cadence data

Published online by Cambridge University Press:  09 September 2016

Hiroyuki Maehara*
Affiliation:
Okayama Astrophysical Observatory, National Astronomical Observatory of Japan, 3037-5 Honjo, Kamogata, Asakuchi, Okayama, Japan, 719-0232
Takuya Shibayama
Affiliation:
Institute for Space-Earth Environmental Research, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, Japan, 464-8601
Yuta Notsu
Affiliation:
Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, Japan, 606-8502
Shota Notsu
Affiliation:
Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, Japan, 606-8502
Satoshi Honda
Affiliation:
Center for Astronomy, University of Hyogo, 407-2, Nishigaichi, Sayo-cho, Sayo, Hyogo, Japan, 679-5313
Daisaku Nogami
Affiliation:
Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto, Japan, 606-8502
Kazunari Shibata
Affiliation:
Kwasan and Hida Observatories, Kyoto University, Yamashina-ku, Kyoto, Japan, 607-8471
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We searched for superflares on solar-type stars using the Kepler short-cadence (1-min sampling) data in order to detect superflares with short duration. We found 187 superflares on 23 solar-type stars whose bolometric energy ranges from the order of 1032 erg to 1036 erg. Using these new data combined with the results from the data with 30-min sampling, we found the occurrence frequency (dN/dE) of superflares as a function of flare energy (E) shows the power-law distribution (dN/dEE−α) with α=1.5 for 1033 < E < 1036 erg. The upper limit of energy released by superflares is basically comparable to a fraction of the magnetic energy stored near starspots which is estimated from the amplitude of brightness variations. We also found that the duration of superflares (τ) increases with the flare energy (E) as τ ∝ E0.39±0.03. This can be explained if we assume the time-scale of flares is determined by the Alfvén time.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2016 

References

Antia, H. M., Bhatnagar, A., & Ulmschneider, P. 2003, Lectures on Solar Physics (Berlin: Springer Verlag) p. 133 CrossRefGoogle Scholar
Aschwanden, M. J., Tarbell, T. D., & Nightingale, R. W., et al. 2000, ApJ, 535, 1047 CrossRefGoogle Scholar
Aschwanden, M. J., Xu, Y., & Jing, J. 2014, ApJ, 797, 50 CrossRefGoogle Scholar
Brown, T. M., Latham, D. W., Everett, M. E., & Esquerdo, G. A. 2011, ApJ, 142, 112 Google Scholar
Christe, S., Hannah, I. G., & Krucker, S., et al. 2008, ApJ, 677, 1385 CrossRefGoogle Scholar
Crosby, N. B., Aschwanden, M. J., & Dennis, B. R. 1993, Solar Phys., 143, 275 Google Scholar
Emslie, A. G., Dennis, B. R., & Shih, A. Y., et al. 2012, ApJ, 759, 71 Google Scholar
Gilliland, R. L., Jenkins, J. M., & Borucki, W. J., et al. 2010, ApJ (Letters), 713, L160 Google Scholar
Huber, D., Silva Aguirre, V., & Matthews, J. M., et al. 2014, ApJS, 211, 2 Google Scholar
Koch, D. G., Borucki, W. J., & Basri, G., et al. 2010, ApJ (Letters) 713, L79 CrossRefGoogle Scholar
Landini, M., Monsignori Fossi, B. C., Pallavicini, R., & Piro, L. 1986, A&A, 157, 217 Google Scholar
Maehara, H., Shibayama, T., & Notsu, S., et al. 2012, Nature, 485, 478 Google Scholar
Maehara, H., Shibayama, T., & Notsu, Y., et al. 2015, Earth, Planet and Space, 67, 59 Google Scholar
McQuillan, A., Mazeh, T., & Aigrain, S. 2014, ApJS, 211, 24 Google Scholar
Nogami, D., Notsu, Y., & Honda, S., et al. 2014, PASJ, 66, L4 Google Scholar
Notsu, Y., Shibayama, T., Maehara, H., et al. 2013, ApJ, 771, 127 Google Scholar
Notsu, Y., Honda, S., & Maehara, H., et al. 2015, PASJ, 67, 33 Google Scholar
Sammis, I., Tang, F., & Zirin, H. 2000, ApJ, 540, 583 Google Scholar
Schaefer, B. E. 1989, ApJ, 337, 927 Google Scholar
Schaefer, B. E., King, J. R., & Deliyannis, C. P. 2000, ApJ, 529, 1026 Google Scholar
Shibata, K. & Magara, T. 2011, Living Reviews in Solar Physics, 8, 6 Google Scholar
Shibata, K., Isobe, H., & Hillier, A., et al. 2013, PASJ, 65, 49 Google Scholar
Shibayama, T., Maehara, H., & Notsu, S., et al. 2013, ApJS, 209, 5 CrossRefGoogle Scholar
Shimizu, T. 1995, PASJ, 47, 251 Google Scholar
Smith, J. C., Stumpe, M. C., & Van Cleve, J. E., et al. 2012, PASP, 124, 1000 Google Scholar
Strassmeier, K. G. 2009, A&AR, 17, 251 Google Scholar
Stumpe, M. C., Smith, J. C., & Van Cleve, J. E., et al. 2012, PASP, 124, 985 Google Scholar
Veronig, A., Temmer, M., & Hanslmeier, A., et al. 2002, A&A 382, 1070 Google Scholar