GCN Circular 4368
J. S. Bloom (UC Berkeley) reports: We have reduced the second epoch of our PAIRITEL imaging (beginning 2005-12-21 03:02:32 UTC; total integration = 690 sec) and detect the source mentioned in GCN 4367 in a stacked mosaic. The source appears to be best detected in the full stack J-band image at a revised position of J2000: 21:54:48.662 +16:53:26.97 The uncertainty relative to the USNOB1.0 is 180 mas in each coordinate (the previous two circulars were based upon an astrometric match using far fewer 2MASS sources in the field). This position is 1.41 arcsec from the Burrows et al. XRT position (GCN 4366). Because the source is observed near the detection level, we cannot confirm fading behavior at this time. Still, given the proximity to the XRT location, we advance that this source is the IR counterpart to GRB 051221 (GCN 4363). If so, this would be the first infrared counterpart detected for a short-hard GRB. This message may be cited.