From: Dibyendu Nandi [mailto:nandi@mithra.physics.montana.edu] Sent: Wednesday, November 26, 2003 5:16 PM To: Richard Canfield Subject: REU Projects Determining the role of twists (local alpha) and its evolution in flaring activity of solar active regions. Aim A study of what characteristics distinguish active regions that tend to evolve according to Taylor's hypothesis from other ARs that do not follow Taylor's hypothesis. Taking a closer look at evolution of local alpha maps over solar active regions and co-spatial flaring activity, to see if localized gradients in alpha initiate flaring acitivity over and across these regions and determine whether those gradients are smoothed out after the flaring activity. Plan of Study Go back to the Hahn database and construct two subset of flare productive ARS, one that showed a decrease in their variance over the flaring period, and a second that did not show a decrease in variance. a) Study the state of flux emergence in these two different datasets to see whether these two subsets can be distinguished by their flux evolution. That is whether the flux was increasing during the duration over which the HSP twist evolution study was done, or was the flux decreasing, or was it at a same level. Flux evolution data can be obtained from either the GOES database or from any Magnetogram. b) Study if the above ARs were evolving in isolation during the period of HSP twist observations, or were they interacting with nearby ARs via overlying loops making the flux systems deviate from a closed flux system (which would make Taylor's hypothesis invalid in these systems). Select a few candidate ARs from the subset which showed a decrease in their overall variance during the flaring activity. The selection criterion for these candidate ARs should be such that; 1) there was at least one stand alone major flare durig the period of the HSP twist evolution study; 2) HSP magnetograms exist as close as possible before and after the flare (this would be a day at best, i am not sure whether thats good enough???). 3) Signatures of that flare (brightening or surges etc) was observed by an instrument that has similar resolution and similar field of view as the HSP instrument (MCCD or any other instrument???) Construct contour maps of local alpha on the heliographic coordinate system for the before and after magnetograms. Superimpose the flare image on both the before and after HSP local alpha contours. Repeat this procedure for all the candidate ARs that were selected using the earlier criterion building many such alpha maps with superimposed flare images. Study if the flaring is cospatial with regions of large gradients in the alpha maps and whether these gradients got smoothed out at the particular places at which the flaring occurred. This will tell us if there is evidence that gradients in alpha drives flaring activity and how the latter reorganizes the former.