GCN Circular 6122
Subject
GRB 070220: ART-3 Optical and NIR limits
Event
Date
2007-02-21T07:53:10Z (19 years ago)
From
Ken ichi Torii at Osaka U <torii@ess.sci.osaka-u.ac.jp>
K. Torii, S. Tanaka, and H. Tsunemi (Osaka U.) report:
The error region of GRB 070220 (Stamatikos et al. GCN 6114;
Beardmore et al. GCN 6118) was observed with the 14 inch
ART-3a and 0.35 m ART-3b, both located in Toyonaka, Osaka.
The imaging started at 2007 Feb. 20, 09:27:03 UT (4.7 hours
after the burst) in Ic band (ART-3a), and at 09:55:44 UT in
J band (ART-3b equipped with thermoelectrically cooled
InGaAs array). We do not detect neither optical nor near
infrared counterpart for the X-ray afterglow (GCN 6114,
6118), and derive the following 3 sigma upper limits
relative to USNO-B1.0 I2 and 2MASS J magnitudes.
-----------------------------------------
StartUT Filter Limit Exposure
=========================================
09:53:18 Ic 19.4 60s x 75
09:55:44 J 14.4 20s x 200
11:12:03 Ic 19.4 60s x 100
=========================================