[vsnet-grb-info 17149] GRB 151027A: Early RAPTOR Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18495
SUBJECT: GRB 151027A: Early RAPTOR Observations
DATE:    15/10/27 18:16:09 GMT
FROM:    James Wren at LANL  <jwren at lanl.gov>

J. Wren, W.T. Vestrand, P. Wozniak, and H. Davis,
of Los Alamos National Laboratory report:

The RAPTOR network of robotic optical telescopes made follow-up observations
of Swift trigger 661775 (Maselli et al., GCN 18478).  Our narrow-field
instruments in Los Alamos, NM USA, began imaging at 03:58:48.01 UT (23.86 s
after the BAT trigger time).  From the first frame we detected a bright optical
counterpart at the location reported by UVOT.  Starting with a magnitude of R~13.7
the RAPTOR telescopes measured a complex, fading lightcurve with seveal
re-brightening intervals.