GCN Circular 6897
Subject
GRB 071010B: Optical Detection
Date
2007-10-12T01:52:16Z (17 years ago)
From
Myungshin Im at Seoul Nat U <mim@astro.snu.ac.kr>
M. Im, I. Lee (Seoul National University), and Y. Urata
(Saitama University) on behalf of the EAFON team:
Using the Mt. Lemmon (Arizona, US) 1.0m telescope
operated by the Korea Astronomy Space Science Institute,
we observed the field of GRB071010B (GCN 6871,
Markwardt et al.) beginning at 11:19:26 UT on Oct 11,
or 14.3 hrs after the trigger.
From a stacked image of four, 5 min frames in the R-band,
we detect the OT (Oksanen GCN 6873, Kann et al. GCN 6884)
with a high significance (S/N > 15) at the position
they reported. Compared to the non-detection
report at 13.6 hrs after the trigger (GCN 6893),
our detection suggests re-brightening of OT.
A preliminary photometry of the object using USNO B1.0
R2 mag of two stars near the OT is given below
(aperture mag with 6" diameter circle).
t_start (UT) Filter exp (sec) R-mag err
-----------------------------------------------------
11:19:26 R 4x300 19.8 0.08 (uncertain)
We will report later, a more careful analysis of the BVR
images taken during the same period.