Internal and external reconnection in a series of homologous solar flares

Details Internal and external reconnection in a series of homologous solar flares Internal and external reconnection in a series of homologous solar flares

Nov 2001

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001jgr...10625227s&link_type=abstract

Journal of Geophysical Research, Volume 106, Issue A11, p. 25227-25238

Astronomy and Astrophysics

Astrophysics

29

Solar Physics, Astrophysics, And Astronomy

Scientific paper

Using data from the extreme ultraviolet imaging telescope (EIT) on SOHO and the soft X-ray telescope (SXT) on Yohkoh, we examine a series of morphologically homologous solar flares occurring in National Oceanic and Atmospheric Administration (NOAA) active region 8210 over May 1-2, 1998. An emerging flux region (EFR) impacted against a sunspot to the west and next to a coronal hole to the east is the source of the repeated flaring. An SXT sigmoid parallels the EFR's neutral line at the site of the initial flaring in soft X rays. In EIT each flaring episode begins with the formation of a crinkle pattern external to the EFR. These EIT crinkles move out from, and then in toward, the EFR with velocities ~20 km s-1. A shrinking and expansion of the width of the coronal hole coincides with the crinkle activity, and generation and evolution of a postflare loop system begins near the time of crinkle formation. Using a schematic based on magnetograms of the region, we suggest that these observations are consistent with the standard reconnection-based model for solar eruptions but are modified by the presence of the additional magnetic fields of the sunspot and coronal hole. In the schematic, internal reconnection begins inside of the EFR-associated fields, unleashing a flare postflare loops, and a coronal mass ejection (CME). External reconnection, first occurring between the escaping CME and the coronal hole field and second occurring between fields formed as a result of the first external reconnection, results in the EIT crinkles and changes in the coronal hole boundary. By the end of the second external reconnection, the initial setup is reinstated; thus the sequence can repeat, resulting in morphologically homologous eruptions. Our inferred magnetic topology is similar to that suggested in the ``breakout model'' of eruptions [Antiochos, 1998], although we cannot determine if our eruptions are released primarily by the breakout mechanism (external reconnection) or, alternatively, primarily by the internal reconnection.

Affiliated with

Also associated with

No associations

Rating

Internal and external reconnection in a series of homologous solar flares does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Internal and external reconnection in a series of homologous solar flares, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Internal and external reconnection in a series of homologous solar flares will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1555011