GCN Circular 7568
Subject
GRB 080330: RAPTOR detection of prompt optical flash
Event
Date
2008-04-07T20:55:40Z (18 years ago)
From
James Wren at LANL <jwren@nis.lanl.gov>
J. Wren, W.T. Vestrand, P.R. Wozniak, H. Davis
of Los Alamos National Laboratory report:
Our RAPTOR telescopes responded to Swift trigger 308041
(Mao et al., GCN 7537) at 03:41:39.93 UTC, 23.1 seconds
after the trigger. Our observations show an optical flash
(about 10 s duration) at T ~ 60 s that is simultaneous
with the fourth gamma-ray peak detected by that BAT
(Markwardt et al., GCN 7549). Subsequently, we detect the
rise of an optical afterglow starting at T ~ 150 s that
levels off to a flat plateau at around T ~ 300 s and then
starts to rapidly decay after about T ~ 2000 s. The
unfiltered measurements reported in the following table
are calibrated to the USNO-B1 R band.
t-mid(s) exp(s) mag mag-err
-----------------------------------------
38.78 31.4 (18.3) 5 sigma limit
58.88 5.0 17.46 0.22
83.15 31.3 (18.4) 5 sigma limit
141.96 22.7 17.62 0.10
294.80 22.7 17.03 0.07
504.74 15.0 17.15 0.06