RHESSI/SOHO/TRACE Workshop

Working Group 5 - Ribbons and Footpoints

[Updated November 9, 2004: events, biblio]
[Updated November 16, 2004: events, archive, page layout]
[Updated November 16, 2004: archive]
[Updated November 30, 2004: links to data]
[Updated December 1, 2004: program organization]
[Updated December 2, 2004: link to TRACEpod]

This group will concentrate on the behavior of solar flares in the lower solar atmosphere, ranging from hard X-ray footpoints and white-light flares to "spreading moss" and regular moss. This is taken to include a very interesting aspect of "ribbons and footpoints," namely how they guide us to the evolution of coronal structure. This ("reconnection") is the focus of Working Group 2, so we will have overlap sessions with this WG. Please see the description of Group 5's activities for further background.

The WG5 program focuses the discussions into two topic areas as defined here:

• Topic area A: the physics of the lower solar atmosphere of flaring coronal loops, wherein we hope to gain an understanding of the novel gamma-ray, IR, and submillimeter data now available.
• Topic area B: the coronal development that we can infer based upon the evolution of ribbon and footpoint sources, as well as the direct coronal observations.

Events for study

The following list has brief comments by Karel on the TRACE data. Please see his detailed commentary, with links to movies and other material, on his unified TRACEpod page. Hugh has checked that RHESSI had good coverage for these events. The October 28, 2003 event and (v. recent) Nov. 10 event are especially worthwhile because of the gamma-ray observations. Karel suggests that events A, C, and D have top priority.

• A. 2002/04/21 00:43UT X1.5 Complex, well-defined, moving ribbons; near limb
• B. 2003/08/25 02:59UT C3.6 Filament eruption with some spreading moss
• C. 2003/10/28 09:51UT X17. Good coverage
• D. 2004/07/15 18:24UT X1.6 Nice ribbon footprints, but with little motion
• E. 2004/11/10 02:13UT X2.5 Good coverage, TRACE at 1600

NOAA events listings for events [A], [B], [C], [D], [E]
Magnetic environments for events [A], [B], [C], [D]
TRACE movies for events (.mov and .qt) [A] [B] [C] [C] [C] [D] [D] [E] by wavelength if multiple (may be large files).

TRACEpod reviews
RHESSI coverage for these events
SAO flare catalog with TRACE data for some of the events

Literature

"Numerical simulations of impulsively heated solar flares," Mariska et al. (1989)
"TRACE and Yohkoh Observations of a White-Light Flare" Metcalf et al. (2003)
"On the Nature of the ``Moss'' Observed by TRACE" Martens et al. (2000)
"First Gamma-Ray Images of a Solar Flare" Hurford et al. (2003)
"Hard X-Ray Source Motions in the 2002 July 23 Gamma-Ray Flare" Krucker et al. (2003)
"Tracking of TRACE ultraviolet footpoints," Fletcher et al. (2004)
"RHESSI e+-e- Annihilation Radiation Observations: Implications for Conditions in the Flaring Solar Chromosphere" Share et al. (2004)