Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 468

GRB991216 Optical Observations
1999-12-17T06:44:00Z (24 years ago)
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

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."
Looking for U.S. government information and services? Visit