TITLE: GCN CIRCULAR NUMBER: 468 SUBJECT: GRB991216 Optical Observations DATE: 99/12/17 06:44:00 GMT FROM: Brad Schaefer at Yale U Bradley E. Schaefer (Yale) and Patrick Seitzer (Michigan) report: "We have obtained R-band and V-band images of GRB991216 and find no transient source in a comparison with the Digital Sky Survey. The first images were taken at 23:45 UT as 60 second V-band and R-band images with the Schmidt telescope on CTIO. The next image was a 10 minute R-band image with the Yale 1m telescope on CTIO starting at 23:52 UT (over a 10.2'X10.2' FOV). These images start 7.6 hours after the burst. The comparison with the Digital Sky Survey, has the usual difficulties that (a) the DSS does not go as deep as our images, (b) color effects near the DSS threshold make for a fuzzy limit. We have already taken BVRI images with the CTIO Schmidt and UBVRIK images with the Yale 1m. We are now repeating these sequences to allow for the detection of variable sources. With GRB991216 being one of the all-time brightest BATSE bursts, the ratio of the gamma-ray luminosity to the optical afterglow luminosity is at least roughly one order of magnitude larger than for any other known burst. It is often convenient to have a 'proper name' for sources frequently discussed, so whimsically, we propose that GRB991216 be informally called the 'Beethoven Burst' in honor of the composer's birthday."