[vsnet-grb-info 16768] GRB 150722A: LCOGT-Sutherland observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18049
SUBJECT: GRB 150722A: LCOGT-Sutherland observations
DATE:    15/07/23 09:00:59 GMT
FROM:    Simone Dichiara at Ferrara U/Italy  <dichiara at fe.infn.it>

S. Dichiara, C. Guidorzi (U. Ferrara), D. Kopac (LJMU),
on behalf of a large collaboration report:

One of the LCOGT 1-m telescopes in Sutherland (South Africa)
began observing GRB 150722A (Marshall et al. GCN 18042)
on July 22 at 17:01:14 UT, i.e. ~7 hours after the BAT
trigger with the r' and i' filters.

Within the XRT error circle (Evans et al. GCN 18044)
we found no new source down to the following limit:

Mid time from  Total Exp   Filter    Magnitude
trigger (hr)   (s)
-------------------------------------------------
7.46           120x15        r'        > 20.0
7.90           120x6         i'        > 18.8
-------------------------------------------------

Values have been calibrated against nearby USNOB-1 stars
(R2 and I).