TITLE:   GCN CIRCULAR
NUMBER:  30386
SUBJECT: GRB 210619B: ALMA detection
DATE:    21/07/06 02:19:43 GMT
FROM:    Tanmoy Laskar at U of Bath  <tanmoylaskar@gmail.com>

T. Laskar (University of Bath), K. D. Alexander (Northwestern), E. Berger
(Harvard), W. Fong (Northwestern), R. Margutti (Northwestern), C. G.
Mundell (University of Bath), and P. Schady (University of Bath) report on
behalf of a larger collaboration:

"We observed GRB 210619B (D'Avanzo et al. GCN 30261) with the Atacama Large
Millimeter/Submillimeter Array (ALMA) at 97.5 GHz beginning on 2021 June 25
06:53:48 UT (5.29 days after the burst). ALMA observations of this burst
were delayed due to a major snowstorm at the array.

Preliminary analysis reveals a mm source with flux density of ~ 0.1 mJy at
position:

RA (J2000) = 21:18:52.349 (+/- 0.002)
Dec (J2000) = +33:51:01.40 (+/- 0.04)

consistent with the X-ray position (Beardmore et al. GCN 30267) and optical
position (D'Avanzo et al., GCN 30261; Kuin et al. GCN 30278).

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