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GCN Circular 3322

GRB 050502: ROTSE-III Detection of Possible Counterpart
2005-05-02T02:55:44Z (19 years ago)
Sarah Yost at U.Michigan <>
S.A. Yost, H. Swan (U Mich), B. A. Schaefer (Louisiana State), K. Alatalo
(U Mich) report  on behalf of the ROTSE collaboration:

ROTSE-IIIb, located at McDonald Observatory, Texas, responsed to GRB
050502 (Integral trigger 2484) 23.3 s after the burst (5.0s after the GCN
notice time), in conditions of variable clouds across the field. The
unfiltered images are calibrated relative to USNO A2.0. Despite the
changes in limiting magnitude due to the clouds, we see a 14.3rd
magnitude, definitely fading source at:

	13:29:46.3 +42:40:27.7 (J2000)

The source is not visible in DSS (2nd epoch), 2MASS, or the MPChecker
database. It is at ~14.3 mag, around 23.3 s after the burst in an image
with a limiting magnitude of approximately 14.9. It is presently at ~
18.5th mag, ~ 1000 sec post-burst.

Continuing observations are in progress.
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