Solar Physics

, Volume 183, Issue 2, pp 359–368 | Cite as

Weakly polarized microwave sources in active regions prior to large X-ray flares

  • A.M. Uralov
  • R.A. Sych
  • V.L. Shchepkina
  • G.N. Zubkova
  • G. Ya. Smolkov
Article

Abstract

The data set archive of the Siberian Solar Radio Telescope was used to synthesize two-dimensional images of more than 50 active solar regions where X-ray flares occurred. Reasonably bright microwave sources with a relatively low level of circular polarization were found to be present in 2/3 of cases prior (days, hours) to the flare. Such characteristics are normally inherent in sources located above the polarity inversion line of the photospheric magnetic field. This result, which has been obtained for the first time using such a representative data set, confirms the significance of these sources in the context of X-ray flare formation.

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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • A.M. Uralov
    • 1
  • R.A. Sych
    • 1
  • V.L. Shchepkina
    • 1
  • G.N. Zubkova
    • 1
  • G. Ya. Smolkov
    • 1
  1. 1.Institute of Solar-Terrestrial PhysicsIrkutskRussia

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