GCN Circular 32809
Subject
GRB221009A: LBT optical imaging
Date
2022-10-20T15:24:03Z (3 years ago)
From
Andrea Rossi at INAF <andrea.rossi@inaf.it>
A. Rossi, E. Maiorano (INAF-OAS), D. B. Malesani (Radboud Univ. and
DAWN/NBI)on behalf of the CIBO collaboration, F. Cusano (INAF-OAS),��and
D. Paris (INAF-OA Roma), report:
We observed the field of GRB 221009A (Dichiara et al., GCN 32632; Kennea
& Williams, GCN 32635; Veres et al.,��GCN 32636; Bissaldi et al., GCN
32637; Svinkin et al., GCN 32641; Ursi et al., GCN Circ. 32650)
simultaneously in the blue and red arms with the g'+r' and g'+i'��bands
with the MODS instrument mounted on LBT (Mt Graham, AZ, USA). We
observed for 22 min per arm at the midtime 03:11 UT on 2022-10-18, 8.58
days after the burst trigger. Observations were performed under modest
weather conditions with an average seeing of ~1" but high humidity and
passing cirrus.
We clearly detect the afterglow and we preliminary measure
r=21.63+-0.02 (AB system),
calibrated against Pan-STARRS field stars.
We acknowledge the excellent support from the LBTO and LBT-INAF staff,
particularly A. Becker and D. G. Huerta in obtaining these observations.