From: "Loren W. Acton" Subject: Thick filter starbursts. Hello, I found some useful thick filter starburst images in 1992. Haven't yet looked more recently. Be A bunch of 15 sec QR images spanning the interval 28-JUN-92 23:28 - 23:54. I haven't examined these for pre-flare correction images yet. Al12 A dandy 60 sec HR starburst of an east limb flare at 23-NOV-92 02:46:52 with 2 good pre-flare images the same orbit. This one I've analyzed. For the thick Al starburst the fits yield: Scattering including rays and between rays Fitted expression: Signal = 1.3e+06*R^(-2.31) per pixel. Scattering avoiding rays Fitted expression: Signal = 1.2e+06*R^(-2.27) per pixel. Scattering beneath rays Fitted expression: Signal = 1.3e+07*R^(-2.93) per pixel. The power-law fits are quite good. I used azimuth_avg.pro to do the fitting to the difference image. Length units are HR pixel. Unfortunately, it will not be possible to normalize the scattering to the flare intensity precisely because the PFI did not get onto the flare region until 23-NOV-92 02:51:46 or 5 minutes after the starburst image. However, the Al12 2.6 sec exposure at 23-NOV-92 02:44:4 is only slightly saturated and the GOES plot increases only 7% between them so it may be possible to guess the flare brightness fairly well. Cheers, Loren