TITLE: GCN CIRCULAR NUMBER: 35968 SUBJECT: X-ray transient EP240315a: ATCA detection of radio counterpart DATE: 24/03/20 22:45:33 GMT FROM: James Leung at U. Toronto / HUJI J. K. Leung (U. Toronto/HUJI), R. Ricci (INAF-IRA), D. Dobie (Swinburne/OzGrav), E. Troja (U. Rome) We observed the field of AT2024eju (Srivastav et al., GCN35932), the likely optical counterpart to the fast X-ray transient EP240315a (Zhang et al., GCN35931), with the Australia Telescope Compact Array (ATCA) under project code CX564. The observations were taken on two consecutive days, from 2024-03-19 06:30 UT to 2024-03-19 09:00 UT and from 2024-03-20 06:30 UT to 2024-03-20 09:30 UT, both at 5.5 and 9 GHz. In our preliminary analysis, we detect a radio source at both 5.5 and 9 GHz, with a flux density of ~0.1mJy. The position of the source is consistent with that of EP240315a (Zhang et al., GCN35931), AT2024eju (Srivastav et al., GCN35932), and the radio counterpart detected at 3 GHz by MeerKAT (Carotenuto et al., GCN35961). Further ATCA observations are planned. We thank the CSIRO Space and Astronomy staff, in particular Jamie Stevens, for supporting these observations in a timely manner. 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.