[vsnet-grb-info 4393] GRB 070306: ART-3 early optical and near infrared constraints

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6175
SUBJECT: GRB 070306: ART-3 early optical and near infrared constraints
DATE:    07/03/07 04:25:57 GMT
FROM:    Ken ichi Torii at Osaka U  <torii at ess.sci.osaka-u.ac.jp>

 The error region of GRB 070306 (Pandey et al. GCN 6169; Page et
al. GCN 6172; Barthelmy et al. 6173) was observed with the ART-3a and
ART-3b under the partly cloudy condition.

 The imaging started at 2007 March 6, 16:43:00 UT (92 s after the
trigger) in Ic band (ART-3a), and at 16:43:24 UT (116 s after the trigger)
in J band (ART-3b). We do not detect neither optical nor near infrared
counterpart for the IR afterglow candidate (Rol et al. GCN
6174). From the useful data sets, we derive the following 3 sigma upper
limits for any new source within the XRT error region (GCN 6172),
relative to USNO-B1.0 I2 or 2MASS J magnitudes.

-----------------------------------------
StartUT         Filter  Limit   Exposure
=========================================
16:52:28        Ic      17.3    60s x 7
16:48:28        J       13.3    20s x 121
=========================================