[vsnet-grb-info 15182] GRB 140628A: Zadko observatory - Gingin optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16474
SUBJECT: GRB 140628A: Zadko observatory - Gingin optical observations
DATE:    14/06/29 01:25:11 GMT
FROM:    Alain Klotz at IRAP-CNRS-OMP  <Alain.Klotz at free.fr>

A. Klotz, D. Turpin (IRAP-CNRS-OMP), D. Macpherson (UWA/ICRAR),
D. Coward (UWA),
M. Boer, B. Gendre, K. Siellez, H. Dereli, O. Bardho (UNS-CNRS-OCA),
A. Williams (PO-UWA), R. Martin (PO-UWA) report:

We imaged the field of GRB 140628A detected by SWIFT
(trigger 602803) with the Zadko robotic telescope (D=100cm)
located at the observatory - Gingin, Australia.

The observations started 6.72h after the GRB trigger.
The elevation of the field increased from
22 degrees above horizon and weather conditions
were poor.

We co-added a series of exposures. We do not
see any optical counterpart at the UVOT position mentioned
by Kuin et al. (GCNC 16472):

t0+6.72h to t0+7.27h : Rlim = 19.9

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.