TITLE: GCN CIRCULAR NUMBER: 45156 SUBJECT: GRB 260706A: ATCA detection of possible radio counterpart DATE: 26/07/14 14:39:13 GMT FROM: James Leung at U. Toronto / HUJI <jamesk.leung@utoronto.ca> J. K. Leung (U. Toronto/HUJI), G. E. Anderson (CSIRO), S. Chastain (TTU), L. Rhodes (TSI/McGill), A. Gulati (U. Sydney), A. J. van der Horst (GWU) on behalf of the PanRadio GRB collaboration We performed observations of GRB 260706A, which was detected by SVOM/ECLAIRs (Alaux et al., GCN 45089) and Fermi/GBM (Fermi GBM team, GCN 45088; Trigg et al., GCN 45093), using the Australia Telescope Compact Array (ATCA) from 14:30 - 23:00 UT on 11 July 2026 (~5.1 days post-burst) using the 4cm (4-12 GHz) receiver. Our observations were centred on the position of the uncatalogued X-ray source found in EP-FXT follow-up observations (Liang et al., GCN45097; Pillas et al., GCN 45114). In our preliminary analysis, we detect a radio source at ~0.2 mJy at 8 GHz with a spectral index of ~1.5 indicating that the radio counterpart is likely to be self-absorbed at this epoch. We measured the position of the radio source to be: RA (J2000)=2:15:15.4 DEC (J2000)=-49:09:02.7 with a positional uncertainty radius of ~0.5". No previous radio source was detected at this position in the Rapid ASKAP Continuum Survey (RACS; McConnell et al., PASA, 37, e048). The radio source is ~2.7" away from the reported position of the EP-FXT uncatalogued X-ray source position (Liang et al., GCN45097), but is consistent within its ~10" positional uncertainty radius. It is the only radio source detected above the 5-sigma = 30 microJy/beam within the SVOM/ECLAIRs error circle (Alaux et al., GCN 45089). We therefore suggest this source is possibly the radio counterpart to GRB 260706A. Further observations are planned. We thank the CSIRO Space and Astronomy staff for supporting these observations. We acknowledge the Gomeroi people as the traditional owners of the Observatory site. The Australia Telescope Compact Array is part of the Australia Telescope National Facility (https://ror.org/05qajvd42) which is funded by the Australian Government for operation as a National Facility managed by CSIRO. View this GCN Circular online at https://gcn.nasa.gov/circulars/45156. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...