• CHAE JONGCHUL (Department of Astronomy and Space Science, Chungnam National University, Big Bear Solar Observatory, NJIT) ;
  • MOON YONG-JAE (Big Bear Solar Observatory, NJIT, Korea Astronomy Observatory) ;
  • PARK SO-YOUNG (Department of Astronomy and Space Science, Chungnam National University)
  • Published : 2003.06.01


Observations have indicated that magnetic reconnect ion may occur frequently in the photosphere and chromosphere as well as in the solar corona. The observed features include cancelling magnetic features seen in photospheric magnetograms, and different kinds of small-scale activities such as UV explosive events and EUV jets. By integrating the observed parameters of these features with the Sweet-Parker reconnect ion theory, an attempt is made to clarify the nature of chromospheric magnetic reconnection. Our results suggest that magnetic reconnect ion may be occurring at many different levels of the photosphere and chromosphere without a preferred height and at a faster speed than is predicted by the Sweet-Parker reconnect ion model using the classical value of electric conductivity. Introducing an anomalous magnetic diffusivity 10-100 times the classical value is one of the possible ways of explaining the fast reconnect ion as inferred from observations.


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