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GCN Circular 3327

GRB 050502: Confirmed variability of the afterglow candidate +
2005-05-02T07:11:15Z (19 years ago)
Josh Bloom at Harvard/CFA <>
C. Blake (Harvard) and J. S. Bloom (UCB) report:

PAIRITEL has continued to image the Yost et al. optical candidate
afterglow (GCN #3322). We confirm that the IR source (#3326) initially
faded, strongly confirming the hypothesis from Yost et al. In
particular, from T+47min to T+94 min the source faded by ~1.1 mag in
J. But from T+94 min to T+121 min, there is some evidence for
brightening by ~0.1 mag in J-band. A similar result is found in H and

Based on an astrometric tie of 2MASS to a 141 sec J-band image from
(start) 2005-05-02 02:52:40 UT, we find

  IRT:  RA = 13:29:46.33, Dec = 42:40:27.3    --Offset to IRT--
  A :   RA = 13:29:42.78, Dec = 42:40:49.2  21.83"   S, 39.19" E
  B:    RA = 13:29:44.23, Dec = 42:38:13.1  134.20"  N, 23.21" E

The uncertainty in the absolute WCS is ~0.5 arcsec.  Sources A and B are
nearby bright sources suitable for blind offset spectroscopy."
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