TITLE: GCN CIRCULAR NUMBER: 12558 SUBJECT: GRB111107A: ATCA observations - upper limit and a possible detection DATE: 11/11/17 09:28:48 GMT FROM: Paul Hancock at U of Sydney Paul J. Hancock, Tara Murphy (U of Sydney) We observed GRB111107A (GCN12534) with the Australian Telescope Compact Array (ATCA) on Nov 07 at 12 UT (~11 hours after the GRB trigger). At 9GHz there is no sign of any emission from the GRB above a 3ó limit of 200uJy. At 5.5GHz there appears to be a 4ó source at 300+/-40uJy at the UVOT location of the GRB (GCN 12538). In both cases the measurement of the possible GRB flux is complicated by the presence of one or more confusing radio sources in the field of view. Further observations are planned. We thank the observatory staff for scheduling and supporting these observations.