GCN Circular 42243
Subject
GRB 251013C: ALMA detection
Event
Date
2025-10-14T03:51:49Z (3 days ago)
From
Tanmoy Laskar at U of Utah <tanmoylaskar@gmail.com>
Via
Web form
T. Laskar (University of Utah), C. Christy, N. Franz, K. D. Alexander (University of Arizona), E. Berger (Harvard University), R. Chornock (UC Berkeley), H. J. van Eerten (University of Bath), G. Farley (U. Utah), W. Fong (Northwestern University), R. Gill (UNAM), J. Granot (Open University), R. Margutti (UC Berkeley), and P. Schady (University of Bath) report:
“We observed GRB 251013C (Fermi GBM team, GCN 42221; Rakotondrainibe et al., GCN 42222) with the Atacama Large Millimeter/Submillimeter Array (ALMA) at 97.5 GHz beginning on 2025 October 13 at 23:07 UT (5.5 hours after the burst).
Preliminary analysis reveals a mm source with flux density of ~ 0.3 mJy at position:
RA (J2000) = 23:03:20.56
Dec (J2000) = -00:12:37.21
with an uncertainty of 0.02" in each coordinate. This is consistent with the X-ray position (Rakotondrainibe et al., GCN 42222; Evans et al., GCN 42232) and optical position (Palmerio et al., GCN 42223; Masi et al., GCN 42228). Further observations are planned.
We thank the NAASC staff, P2G, AoD, JAO staff, and the entire ALMA team for their help with these observations."