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GCN Circular 12684

GRB 111209A: RAPTOR Limits Before and During the Gamma-ray Emitting Interval
2011-12-15T17:32:20Z (12 years ago)
James Wren at LANL <>
J. Wren, W. T. Vestrand, P. Wozniak, and H. Davis
of Los Alamos National Laboratory report:

The RAPTOR wide-field optical monitors were observing the location of
GRB 111209A (Hoversten et al., GCN 12632) during the gamma-ray emitting
interval as seen by the Swift BAT (Palmer et al., GCN 12640).  Our
system acquired 10 s exposures at 20 s intervals during the entire
emission period.  We have analyzed the the 77 images taken between
T-150 and T+1400 and we do not detect the counterpart to a typical
3-sigma limiting magnitude of 10.3.  Our unfiltered images were
calibrated to the Tycho-2 V-band.
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