TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2280 SUBJECT: GRB 021206, Radio afterglow candidate DATE: 03/06/10 13:09:15 GMT FROM: Dale A. Frail at NRAO D. A. Frail (NRAO) reports on behalf of a larger collaboration: "Using the VLA, we imaged the inner quarter of the initial IPN error box of the exceptionally bright gamma-ray burst GRB 021206 (Hurley et al. GCN#'s 1727, 1728). In initial observations made at 4.86 GHz during the first week after the burst, there was an unresolved radio source with a flux density of ~400 uJy located at r.a.=16:00:46.85, dec.=-09:42:33.5 (J2000), with an uncertainty of about 0.6 arcsec. Subsequent measurements at 4.86 and 8.46 GHz in February and March 2003 showed that the source has faded by a least a factor of five. Future observations are planned to place tighter limits on the flux density of this radio source. Although the magnitude of the radio flux density and the temporal behavior of the light curve are typical of past GRB afterglows, we cannot rule out the possibility (probability <=0.02) that this is an unrelated background variable (Frail et al. AJ, 125, 2299, 2003). Given the recent RHESSI detection of polarized emission from this burst (Coburn & Boggs, Nature, 423, 415, 2003) we encourage further followup optical observations of this candidate afterglow." This message may be cited.