GRB 240619A: detection of a radio counterpart with AMI-LA

We observed the field of GRB 240619a (GCN 36694) with the Arcminute Microkelvin Imager - Large Array (AMI-LA) at 15.5 GHz beginning at UT 13:45:34 on 22-June-2024 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 J1051+2119 was used as an interleaved complex gain calibrator. We detected an unresolved radio source at the position of the afterglow candidate (GCN 36715) with a flux density of about 1.5mJy/beam. The rms noise in the field is about 60uJy/beam. More observations are ongoing. We thank the staff at the Mullard Radio Astronomy Observatory for carrying out these observations and operating the AMI-LA.