GCN Circular 5961
Subject
GRB 061222b, SMARTS optical/IR afterglow observations
Date
2006-12-22T05:31:57Z (18 years ago)
From
Bethany Cobb at Yale U <cobb@astro.yale.edu>
B. E. Cobb (Yale), part of the larger SMARTS consortium, reports:
Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 061222b
(GCN 5957, Racusin et al.), with a mid-exposure time of
2006-12-22 04:42:11 UT, which is ~0.5 hours post-burst.
Several dithered images were obtained in each filter,
with total summed exposure times of 180s in each of BRIYJK and
120s in each of H and V.
In the I-band a dim object is detected with a preliminary
magnitude of I=20.7+/-0.4 at the position of the afterglow
reported by Berger (GCN 5956). This source is not significantly
detected in the J-band to a limiting magnitude of J<18.
Photometry is calibrated with USNO-B1.0 stars in the optical
and 2MASS stars in the IR. Photometry is effect by high background
due to the nearby bright star.