TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  479
SUBJECT: GRB991216
DATE:    99/12/17 23:34:27 GMT
FROM:    Craig Wheeler at U.Texas  <wheel@astro.as.utexas.edu>

D. Andrew Howell, Michael Ward, Lifan Wang, and J. Craig Wheeler of the
University of Texas at Austin report:

The field of GRB991216 was imaged with the 0.8m telescope Prime Focus
Camera at McDonald Observatory.  Three 0.49 sq. deg. 600s Rc exposures 
were obtained centered on the RXTE position reported by Takeshima et al.
The images were taken at Dec 17.153, 17.162, and 17.173 UT under conditions 
of intermittent clouds and high cirrus, with a very rough limiting 
magnitude of 19.2.  The OT reported by Uglesich et al. (GCN Circular #472)
is confirmed, but is so near our magnitude limit that reliable photometry
cannot be done.  We can say that from visual inspection the OT appears 
brighter than most stars listed at 19.1 magnitude in the USNO (red)
catalog, but fainter than stars around 18.5 (the USNO red photgraphic 
magnitudes are derived from scans of POSS-I plates and highly uncertain).  
Therefore our data are consistent with the first epoch data reported 
by Uglesich et al. (R=18.8 at Dec. 17.142).  

This message can be cited.