Hα Dimmings Associated with the X1.6 Flare and Halo Coronal Mass Ejection on 2001 October 19

Astronomy and Astrophysics – Astronomy

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

12

Sun: Activity, Sun: Coronal Mass Ejections (Cmes), Sun: Filaments, Sun: Flares, Sun: Magnetic Fields

Scientific paper

As the optical counterpart of coronal dimmings, we present the first direct evidence of Hα dimmings associated with the X1.6 flare, filament eruption, and coronal mass ejection (CME) that occurred on 2001 October 19. As two main Hα flare ribbons parallel to the erupting filament slowly separated, two other ribbons first quickly expanded near the feet of the filament, then their interiors substantially dimmed and became darker than the preflare brightness. This formed two dimming regions with sharp bright edges. The two Hα dimmings were different from the flare nimbus and the Hα darkenings found by Ellison, McKenna, & Reid and Neidig et al., respectively, but similar to the coronal ``double dimmings'' studied by Sterling & Hudson. The coronal dimmings of the event were also observed in 171 Å images from the Transition Region and Coronal Explorer (TRACE). The 171 Å and Hα dimmings showed very similar evolutions and occurred at the same two sites with opposite magnetic polarities. They formed in the course of the filament eruption, and after the eruption, some 171 Å loops of the postflare arcade developed to connect their inner edges while some loops with footpoints near their outer edges disappeared. Observations from the Solar and Heliospheric Observatory Extreme-ultraviolet Imaging Telescope (SOHO/EIT) showed more extended dimmings associated with the eruption. Only a small portion of EIT dimmings was cospatial with the Hα dimmings, while the major other portion was associated with the disappeared 171 Å loops. These joint observations are interpreted by using the flux rope model of CMEs, in which the Hα dimmings represent the evacuated feet of the erupted flux rope. The mass supply of the halo CME could be coming from both the erupted flux rope itself and the lost material close to the flare footpoint regions as shown by Hα dimmings.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Hα Dimmings Associated with the X1.6 Flare and Halo Coronal Mass Ejection on 2001 October 19 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 Hα Dimmings Associated with the X1.6 Flare and Halo Coronal Mass Ejection on 2001 October 19, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hα Dimmings Associated with the X1.6 Flare and Halo Coronal Mass Ejection on 2001 October 19 will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1087246

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.