Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-13T12:02:47.205Z Has data issue: false hasContentIssue false
  • English
  • Français

Stellar flare diagnostics from multi–wavelength observations

Published online by Cambridge University Press:  26 February 2010

Alexander V. Stepanov ,
Yuri T. Tsap  and
Yulia G. Kopylova
Alexander V. Stepanov
Affiliation:
Pulkovo Observatory, 196140 S.–Petersburg, Pulkovskoye chaussee 65/1, Russia email: stepanov@gao.spb.ru; yulia00@mail.ru
Yuri T. Tsap
Affiliation:
Pulkovo Observatory, 196140 S.–Petersburg, Pulkovskoye chaussee 65/1, Russia email: stepanov@gao.spb.ru; yulia00@mail.ru Crimean Astrophysical Observatory, 98409 Nauchny, Crimea, Ukraine email: yur@crao.crimea.ua
Yulia G. Kopylova
Affiliation:
Pulkovo Observatory, 196140 S.–Petersburg, Pulkovskoye chaussee 65/1, Russia email: stepanov@gao.spb.ru; yulia00@mail.ru
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.

Quasi–periodic pulsations in various wavebands are natural manifestations of emission of stellar flares. We suggest a diagnostic tool of stellar flares based on the coronal seismology and the solar–stellar analogy. Two approaches are used: (I) flare loop as a resonator for MHD oscillations and (II) flare loop as an equivalent electric circuit. Using optical, X–ray, and radio data we obtained flare plasma parameters for the red dwarfs EQ Peg, AT Mic, and AD Leo. The characteristic length of stellar flare loops l ~ R* and their electric currents turned out to be one–two orders of magnitude lager than the solar ones. Advantages of proposed diagnostics in comparison to the scaling law methods are given.

Keywords

stars: late–typeflareplasmasmagnetohydrodynamicsoscillationscoronae
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 5 , Symposium S264: Solar and Stellar Variability: Impact on Earth and Planets , August 2009 , pp. 288 - 291
Copyright
Copyright © International Astronomical Union 2010

References

Bastian, T. S., Bookbinder, J., Dulk, G. A., & Davis, M. 1990, ApJ, 353, 265Google Scholar
Gershberg, R. E. 2005, Solar-type activity in main-sequence stars (Berlin: Springer)Google Scholar
Haisch, B. M. 1983, in: Byrne, P. B. & Rodono, M. (eds.), IAU Colloq. 71: Activity in Red–Dwarf Stars, (D. Reidel Publishing Co.), 255CrossRefGoogle Scholar
Mathioudakis, M., Bloomfield, D. S., Jess, D. B. et al. 2006, A&A, 456, 323Google Scholar
Mitra-Kraev, U., Harra, L. K., Williams, D. R., & Kraev, E. 2005, A&A, 436, 1041Google Scholar
Raassen, A. J. J., Mewe, R., Audard, M., & Güdel, M. 2003, A&A, 411, 509Google Scholar
Roberts, B. 1995, in Advances in Solar System Magnetohydrodynamics, eds. Priest, E. R. and Hood, A. W. (Cambrige: Cambrige University Press), 105.Google Scholar
Stepanov, A. V., Kopylova, Yu. G., Tsap, Yu. T., & Kupriyanova, E. G. 2005, Astron. Lett., 31, 612Google Scholar
Stepanov, A. V., Tsap, Yu. T., & Kopylova, Yu. G. 2006, Astron. Lett., 32, 569CrossRefGoogle Scholar
Tsap, Yu. T. 2006, Kinematika i Fizika Nebesnykh Tel, 22, 40.Google Scholar
West, A. A., Hawley, S. L., Walkowicz, L. M. et al. 2004, AJ, 128, 426CrossRefGoogle Scholar
Zaitsev, V. V., Stepanov, A. V., Urpo, S., & Pohjolainen, S. 1998, A&A, 337, 887Google Scholar
Zaitsev, V. V., Kislyakov, A. G., Stepanov, A. V., Kliem, B., & Furst, E. 2004, Astron. Lett., 30, 319CrossRefGoogle Scholar