Flare Energy Build-up in a Decaying Active Region Near a Coronal Hole

Details Flare Energy Build-up in a Decaying Active Region Near a Coronal Hole Flare Energy Build-up in a Decaying Active Region Near a Coronal Hole

Oct 2009

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009apj...704..341s&link_type=abstract

The Astrophysical Journal, Volume 704, Issue 1, pp. 341-353 (2009).

Astronomy and Astrophysics

Astronomy

10

Sun: Corona, Sun: Filaments, Sun: Flares, Sun: Magnetic Fields, Sun: Photosphere, Sun: X-Rays, Gamma Rays

Scientific paper

A B1.7 two-ribbon flare occurred in a highly non-potential decaying active region near a coronal hole at 10:00 UT on 2008 May 17. This flare is "large" in the sense that it involves the entire region, and it is associated with both a filament eruption and a coronal mass ejection. We present multi-wavelength observations from EUV (TRACE, STEREO/EUVI), X-rays (Hinode/XRT), and Hα (THEMIS, BBSO) prior to, during and after the flare. Prior to the flare, the region contained two filaments. The long J-shaped sheared loops corresponding to the southern filament were evolved from two short loop systems, which happened around 22:00 UT after a filament eruption on May 16. Formation of highly sheared loops in the southeastern part of the region was observed by STEREO 8 hr before the flare. We also perform nonlinear force-free field (NLFFF) modeling for the region at two times prior to the flare, using the flux rope insertion method. The models include the non-force-free effect of magnetic buoyancy in the photosphere. The best-fit NLFFF models show good fit to observations both in the corona (X-ray and EUV loops) and chromosphere (Hα filament). We find that the horizontal fields in the photosphere are relatively insensitive to the present of flux ropes in the corona. The axial flux of the flux rope in the NLFFF model on May 17 is twice that on May 16, and the model on May 17 is only marginally stable. We also find that the quasi-circular flare ribbons are associated with the separatrix between open and closed fields. This observation and NLFFF modeling suggest that this flare may be triggered by the reconnection at the null point on the separatrix surface.

Affiliated with

Also associated with

No associations

Rating

Flare Energy Build-up in a Decaying Active Region Near a Coronal Hole 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 Flare Energy Build-up in a Decaying Active Region Near a Coronal Hole, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flare Energy Build-up in a Decaying Active Region Near a Coronal Hole will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-805377