TITLE:   GCN CIRCULAR
NUMBER:  32803
SUBJECT: GRB 221009A: BOAO NIR detections
DATE:    22/10/19 15:52:11 GMT
FROM:    Myungshin Im at Seoul Nat U  <mim@astro.snu.ac.kr>

Myungshin Im, Gregory S.-H. Paek, Gu Lim, Hyeonho Choi, Sophia Kim (SNU),
Hyun-Il Sung (KASI), Yuji Urata (NCU) on behalf of a larger collaboration

We observed the field of GRB 221009A (Swift detection: Dichiara et al., GCN
32632; Fermi GBM detection: Veres et al., GCN 32636), in J and K filters
with the KASINICS instrument on the 1.8 m telescope of the Bohyunsan
Optical Astronomy Observatory (BOAO), Korea. The observation started at
2022-10-18-11:34 (UT) or JD=2459870.98230324, taking a series of images for
about 1.25 hrs.

We identify the afterglow in the KASINICS images, with a rough photometry
of K ~ 18.6 AB mag. Further observations and analysis are being carried out
to obtain more data and refine the photometry.

We thank the staff of BOAO for carrying out the observation.