TITLE:   GCN CIRCULAR
NUMBER:  36250
SUBJECT: GRB 240419A: Possible ATCA radio detection
DATE:    24/04/23 09:51:22 GMT
FROM:    Gemma Anderson at Curtin U <gemma.anderson@curtin.edu.au>

S. Chastain (UNM), G. E. Anderson (Curtin University), J. K. Leung (U. Toronto/HUJI), L. Rhodes (U. Oxford), S. D. Ryder (Macquarie), A. Gulati (U. Sydney), A. J. van der Horst (GWU), on behalf of the PanRadio GRB collaboration

The Australia Telescope Compact Array (ATCA) performed rapid follow-up observations of GRB 240419A (Siegel et al., GCN 36169) at 5.5, 9, and 18 GHz as part of the Long-term ATCA "PanRadio GRB" follow-up programme C3542 (PI. Anderson). ATCA began observing at 2024-04-19 04:00 UT (2.2 hours post-burst) up until 12:30 UT. In our preliminary analysis, we have a marginal detect of 63 +/- 18 microJy/beam at 18 GHz that is coincident with the enhanced XRT position (Goad et al., GCN 36174). We obtain 3 sigma upper limits of 39 and 42 microJy/beam at 5.5 and 9.0, respectively. 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.