TITLE: GCN GRB OBSERVATION REPORT NUMBER: 195 SUBJECT: GRB 981226: radio variable DATE: 99/01/20 05:07:06 GMT FROM: Dale A. Frail at NRAO D. A. Frail reports on behalf of a larger NRAO/Caltech collaboration: "There is a faint radio source within the NFI error circle (GCN #184) of GRB 981226 at RA = 23h29m37.21s, DEC = -23d55'53.8" with an error of +/-0.5". The source was first detected at the VLA on Jan 3.95 UT with an 8.46 GHz flux density of 169 +/- 28 microJy. It is present but at a weaker level on at least three other epochs (Dec. 29, Jan 7 and Jan 11), where its average flux density is 76 +/- 17 microJy. On January 19.89 UT, the flux density of the source had dropped below detectablity, with an upper limit of 28 microJy. This level of short term variability is characteristic of radio afterglows at early times. In contrast, two other radio sources in the field have remained constant during this same period. We urge optical observers to re-examine this location for any indication of a transient or a faint host galaxy." This message is citeable.