TITLE:   GCN CIRCULAR
NUMBER:  37157
SUBJECT: GRB 240809A: ALMA detection
DATE:    24/08/12 21:44:40 GMT
FROM:    Tanmoy Laskar at U of Bath <tanmoylaskar@gmail.com>

T. Laskar (University of Utah), C. Christy (University of Arizona), K. D.
Alexander (University of Arizona), G. Schroeder (Northwestern University),
C. Peña (University of Utah), E. Berger (Harvard University), R. Chornock
(UC Berkeley), W. Fong (Northwestern University), R. Margutti (UC
Berkeley), and P. Schady (University of Bath) report on behalf of a larger
collaboration:

"We observed GRB 240809A (Evans et al., GCN 37110) with the Atacama Large
Millimeter/Submillimeter Array (ALMA) at 97.5 GHz over two epochs,
beginning on 2024 August 09 19:30 UT and 2024 August 10 23:28 UT, at 11 h
and 39 h after the burst, respectively. Preliminary analysis reveals a
fading mm source, with flux density of ~ 0.1 mJy in the first epoch, which
we identify as the radio counterpart of GRB 240809A. Further observations
are planned.

We thank the JAO staff, AoD, P2G, and the entire ALMA team for their help
with these observations."