[vsnet-grb-info 11657] GRB 120311B: C88 optical limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13050
SUBJECT: GRB 120311B: C88 optical limits
DATE:    12/03/12 18:32:49 GMT
FROM:    Simone Leonini at Monarrenti Obs  <s.leonini at iol.it>

Simone Leonini and Paolo Rosi (Montarrenti Observatory, Siena, Italy) report:

We observed the field of GRB 120311B (Swift trigger 517489, Marshall et al.,
GCN Circ 13038) with 0.53m RC telescope + U47 detector at Montarrenti Observatory
(Siena, Italy, IAU code C88).

The first session of observations was started at 2012-03-12 03:59:24 UT
and stopped at 2012-03-12 04:00:07 UT.  The second session started at 04:11:47 UT
and stopped at 04.12.26 UT (~13 hours after the trigger).

Four unfiltered images of 40s exposure was obtained.  We do not detect
any new point source in the coadded images (limit R~18.9, USNO-B1 catalogue)
within the enhanced XRT error circle (Osborne et al., GCN Circ. 13042).
Target was very low on the horizon.

[GCN OPS NOTE(12mar12): Distribution was delayed by ~3 hrs until an account
could be created.]