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GCN Circular 9224

GRB 090424: ROTSE-III Confimation of Optical Counterpart
2009-04-24T14:35:53Z (15 years ago)
Fang Yuan at ROTSE <>
F. Yuan (U Mich), report on behalf of the ROTSE collaboration:

ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded  
to GRB 090424 (Swift trigger 350311;Cannizzo et al, GCN 9223). The  
first image started at 14:18:41.4 UT, ~6 min after the burst. The  
unfiltered images are calibrated relative to USNO A2.0. We detect a  
fading source at the position consistent with the UVOT OT, at the  
following magnitude:

start UT    	mag     mlim(of image)
14:18:41.4     15.5     17.2

This source is not visible in DSS (second epoch), 2MASS or the  
MPChecker database.

A jpeg image is available at 
  Note that the object marked 12 is the candidate in question.

Continuing observations are in progress.
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