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GCN Circular 9439

GRB 090530A: ROTSE-III Detection of Optical Counterpart
2009-05-30T03:30:24Z (15 years ago)
Heather Flewelling at IfA/Hawaii <>
H. Flewelling (IfA), B. E. Schaefer (Louisiana State), Shashi Pandey (UMich)
report on behalf of the ROTSE collaboration:

ROTSE-IIIb, located at McDonald Observatory, Texas, responded to GRB 090530A
(Swift trigger 353567). The first image was at 03:18:35.8 UT, 17.4 s after
the burst (6.8 s after the GCN notice time). The unfiltered images are
calibrated relative to USNO A2.0. We detect a new object, not visible in the
DSS (second epoch), with coordinates:

     11:57:40.5      +26:35:37.9    (J2000), with positional uncertainty of
1" or better

start UT    	mag     mlim(of image)
03:18:42.7     16.0     16.2

A jpeg image is available at Note that the object
marked 48 is the candidate in question.

Continuing observations are in progress.
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