GCN Circular 9931
Subject
GRB090904B : IRSF NIR upper limit
Date
2009-09-25T02:00:32Z (15 years ago)
From
Kenta Nishimoto at Nagoya U/MOA-II <nishimo@stelab.nagoya-u.ac.jp>
K. Nishimoto, T. Sako(Nagoya Univ.) on behalf of the MOA Collaboration,
M. Kurita on behalf of the IRSF Collabration, T. Yosikawa(Kyoto Univ.),
T. Suenaga(Soken Univ.) report:
We searched for a NIR afterglow of GRB090904B (GCN9881, V. D'Elia et
al.) starting from 17:6:57.7 UT on 2009 Sep 4 (15.71 hours after the burst)
with the SIRIUS on the IRSF 1.4m telescope at SAAO in South Africa.
In images of a 300sec exposure with J, H and Ks filter, we did not find
any object except the reported star (GCN9882, Covino et al and GCN9892,
Nishimoto et al.) within the error circle of the Swift XRT source
position (GCN9887, J.P. Osborne et al.).
Quick estimation of the limiting magnitude calibrated by using 2MASS
catalog:
J > 17.14
H > 16.57
K > 15.79