TITLE: GCN CIRCULAR NUMBER: 14434 SUBJECT: GRB 130418A: WSRT radio observation DATE: 13/04/22 06:50:13 GMT FROM: Alexander van der Horst at U of Amsterdam A.J. van der Horst (University of Amsterdam) reports on behalf of a large collaboration: "We observed the position of the GRB 130418A afterglow at 4.9 GHz with the Westerbork Synthesis Radio Telescope at April 21 13.53 UT to April 22 01.49 UT, i.e. 2.77 - 3.27 days after the burst (GCN 14377). We do not detect a radio source at the position of the optical counterpart (GCN 14384). The three-sigma rms noise in the map around that position is 69 microJy per beam. The formal flux measurement for a point source at the position of the optical counterpart is 34 +/- 23 microJy. We would like to thank the WSRT staff for quickly scheduling and obtaining these observations."