GCN Circular 10150
Subject
GRB 091109B: Optical limits from Watcher
Date
2009-11-09T23:47:07Z (14 years ago)
From
Petr Kubanek at AIO <petr@lascaux.asu.cas.cz>
M. Jel����nek (IAA-CSIC), A. de Ugarte Postigo (INAF-OAB), R. Felletti, L.
Hanlon (UCD Dublin), H. Van Heerden (UOVS, Bloemfontein), P. Kub����nek
(IPL UV, IAA-CSIC) reports on behalf of a large collaboration:
Watcher telescope, located at Boyden Observatory, South Africa,
observed autonomously GRB 091109B (S. R. Oates et al., GCN 10148). We
obtained a set of 5s exposures in clear filter, starting 78s after the
GRB (65s after the notice). We see no new sources in the XRT error box
down to the single-image limiting magnitude of 16.5. Coaddition of
first 120s (mean exposure time 153s after the GRB) of imaging data
improves this limit to ~17.7 calibrated against field USNO-A2.0 R-band
stars. Those results are consistent with ROTSE-III non-detection
(Schaefer et al. GCN 10149).
We note that there is a R~15.3 galaxy 8" North-West of the XRT position,
posibly the host of this short GRB.
Further observations are ongoing. This message can be quoted.