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GCN Circular 6948

GRB 071020A: ROTSE-III Detection of Optical Counterpart
2007-10-20T07:17:21Z (17 years ago)
Brad Schaefer at LSU <>
B. E. Schaefer (Louisiana State), T.A. McKay (U Mich), F. Yuan (U Mich), 
report on behalf of the ROTSE collaboration:

ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB 
071020A (Swift trigger 294835). The first image was at 07:02:52.5 UT, 25.6 
s after the burst (9.5 s after the GCN notice time). The unfiltered images 
are calibrated relative to USNO A2.0. We detect a 13.6 magnitude, fading 
source with coordinates:

     07:58:39.9      +32:51:41.4    (J2000), with positional uncertainty 
of 1" or better

start UT    	mag     mlim(of image)
07:02:52.9     13.6     16.4 

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

A jpeg image is available at

Continuing observations are in progress.
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