[vsnet-grb-info 10384] GRB110318B : MOA optical upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11822
SUBJECT: GRB110318B : MOA optical upper limit
DATE:    11/03/25 16:40:17 GMT
FROM:    Suzuki Daisuke at MOA-II  <dsuke at stelab.nagoya-u.ac.jp>

D. Suzuki (STE Lab. Nagoya Univ.), P.J. Tristram (Mt. John University
Observatory),
S. Kobara, K. Omori, H. Naito and T. Sako (STE Lab. Nagoya Univ.)
on behalf of the MOA Collaboration report :

We searched for an optical afterglow of GRB110318B (GCN 11799, R. Margutti
et al.)
starting from 15:40 UT on 2011 March 18 (13 minutes after the burst)
with the MOA-II 1.8m telescope at Mt.John observatory in New Zealand.
In a single image of a 60 sec exposure with a wideband Red filter (center
wavelength ~ 750nm and FWHM ~ 250nm), we did not find any object
within the error circle of the Swift XRT source position (GCN 11803, P.A.
Evans et al.).
A 3 sigma upper limit is set in the I magnitude at 20.7 mag.

This photometry was done by using the DoPhot and calibrated against
the USNO-B1.0 catalog stars, and not corrected for the Galactic extinction.