TITLE: GCN CIRCULAR NUMBER: 8792 SUBJECT: GRB 090102: WSRT Radio Observations DATE: 09/01/09 16:39:06 GMT FROM: Alexander van der Horst at NASA/MSFC A.J. van der Horst (NASA/MSFC/ORAU), R.A.M.J. Wijers and A.P. Kamble (University of Amsterdam) report on behalf of a larger collaboration: "We observed the position of the GRB 090102 afterglow at 4.9 GHz with the Westerbork Synthesis Radio Telescope at January 8 18.88 UT to January 9 6.86 UT, i.e. 6.66 - 7.16 days after the burst (GCN 8762). We do not detect a radio source at the position of the optical counterpart (GCN 8766). The three-sigma rms noise in the map around that position is 72 microJy per beam. The formal flux measurement for a point source at the position of the optical counterpart is 12 +/- 24 microJy. We would like to thank the WSRT staff for scheduling and obtaining these observations."