Solar Large-Scale Chains Associated with a Number of ISTP/IACG CDAW Eruptive Events

Ilia M. Chertok

Abstract

A novel phenomenon of the large-scale solar activity - relatively weak extended emitting chains and threads with characteristic sizes comparable with the solar disk diameter - has been detected recently on the modified heliograms in the microwave (Nobeyama Radioheliograph), soft X-ray (Yohkoh/SXT), EUV (SOHO/EIT, TRACE), and other ranges. There are grounds to consider that the chains light separators or quasi-separatrix layers between different interacting large-scale magnetic flux systems in the global solar magnetosphere and, in particular, outline large-scale coronal structures involved in the CME process.  In the present report, some features of the chains and their relations to CMEs are illustrated by several eruptive events from the ISTP/IACG Workshop List. It is shown that a noticeable evolution of the large-scale chains can occur during many hours both before and after a CME. It is reasonable to assume that the chains preceding CMEs display energy release resulting from evolving large-scale magnetic structures at the stage when development of these structures is approaching to a CME eruption. On the other hand, the chains following CMEs can result from the post-eruption energy release when magnetic fields in an extended region of the corona, strongly disturbed by a CME eruption, relaxes to its initial state via magnetic reconnection in large-scale coronal current sheets.  Under a high activity it is reasonable to speak about a combination of the high chain and CME activities rather than about an association between some concrete chains and CMEs. Many modified  images and movies with the CME-associated chains, particularly from SOHO/EIT, are presented.
 
 

  Organization: IZMIRAN, Russian Academy of Science
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