TITLE: GCN CIRCULAR NUMBER: 42294 SUBJECT: GRB 251013C: detection of a radio counterpart at 15.5GHz DATE: 25/10/15 16:27:02 GMT FROM: Lauren Rhodes at McGill Lauren Rhodes (McGill/TSI), Andrew Hughes (Oxford), Rob Fender (Oxford), Dave Green (Cambridge), Dave Titterington (Cambridge) report:   We observed the field of the afterglow candidate GRB 251013C (GCN 42221) with the Arcminute Microkelvin Imager Large-Array (AMI-LA) at 15.5 GHz beginning at UT 19:27:08.0 on 14-Oct-2025 for a total of 4 hours. The flux standard 3c286 was used to calibrate the bandpass response and flux scale of the AMI-LA and J2320+0513 was used as an interleaved complex gain calibrator. We detected a point source with a peak flux density of 0.34 +/- 0.08 mJy/beam with a position of RA   =  23h03m20.5+/- 0.2s Dec = -00d12'26+/- 9" Further observations are planned. We thank the staff at the Mullard Radio Astronomy Observatory for carrying out these observations and operating the AMI-LA.