TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4239
SUBJECT: Early RAPTOR measurements of GRB 051109a - the movie.
DATE:    05/11/10 00:37:54 GMT
FROM:    Przemyslaw R. Wozniak at LANL  <wozniak@lanl.gov>

P.R. Wozniak, W.T. Vestrand, J. Wren, R. White, S. Evans
on behalf of the RAPTOR team report:

Starting at 01:12:54.42 UT on November 9, 33.9 seconds after
the Swift BAT trigger, the Raptor-S robotic telescope at
Los Alamos National Laboratory responded to Swift trigger 163136
(Tagliaferri et al., GCN 4213). The automated response was
composed of a series of ten 5-second duration exposures followed
by 20 10-second exposures and finally by 183 30-second exposures.
The unfiltered images show an optical transient at the position
identifed by Rykoff et al. (GCN 4211) that fades from magnitude
R ~15.1 to ~17.5 over the course of 20 minutes. The unfiltered
magnitudes were transformed to the R2 magnitude scale of the
USNO B1.0 catalog. Short animations derived from the RAPTOR images
can be viewed at:

EPISODE I: "The First Four Minutes"
http://www.raptor.lanl.gov/images/GRB051109a/grb051109a_early_movie.gif
EPISODE II: "The Next Half Hour"
http://www.raptor.lanl.gov/images/GRB051109a/grb051109a_late_movie.gif