[vsnet-grb-info 19327] GRB 170419B: Zadko observatory - Gingin optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  21024
SUBJECT: GRB 170419B: Zadko observatory - Gingin optical observations
DATE:    17/04/20 14:19:03 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, (UNS-CNRS-OCA), Gendre B. (UVI - Etelman Obs.),
A. Williams (PO-UWA), R. Martin (PO-UWA)
report:

We imaged the field of GRB 170419B detected by SWIFT
(trigger 748947) with the Zadko robotic telescope (D=100cm)
located at the observatory - Gingin, Australia.

The observations started 13.3h after the GRB trigger.
The elevation of the field decreased from
31 degrees above horizon and weather conditions
were good.

We co-added a series of exposures but we did not find any
optical transcient in the BAT error box provided by
Cholden-Brown et al. (GCNC 21016):

t0+13.3h to t0+13.5h : Rlim = 19.2

Magnitudes were estimated with the nearby NOMAD1 stars
and are not corrected for galactic dust extinction.