[vsnet-grb-info 10427] GRB 110402A: early optical limit by Pi of the Sky

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11864
SUBJECT: GRB 110402A: early optical limit by "Pi of the Sky"
DATE:    11/04/02 10:16:16 GMT
FROM:    Grzegorz Wrochna at Soltan Inst.for Nuclear Studies  <wrochna at fuw.edu.pl>

M.Sokolowski,T.Batsch,A.Majcher,A.Majczyna,K.Nawrocki,J.Uzycki,G.Wrochna (IPJ, Swierk),
M.Cwiok,W.Dominik,L.W.Piotrowski,A.F.Zarnecki (University of Warsaw),
K.Malek,L.Mankiewicz,R.Opiela,M.Siudek,V.Repei (CFT PAN),
G.Kasprowicz,M.Zaremba (Warsaw University of Technology),
from the "Pi of the Sky" collaboration (http://grb.fuw.edu.pl  ).
M. Jelinek and A. J.Castro-Tirado (IAA-CSIC Granada) on behalf of a larger collaboration.

The wide field "Pi of the Sky North" apparatus installed in the BOOTES-1
station at ESAt/INTA-CEDEA in Mazagon (Huelva, Spain;
http://grb.fuw.edu.pl/pi/index.html#piinta_site.htm  )
observed field of GRB 110402A at the time of Fermi-GMB and Swift-BAT triggers.
No new source brighter than 11 mag has been identified on 10s exposures:

t_start - t0      start (UT)  end (UT)     3-sigma limit

       -6           00:12:52    00:13:02     11.0
       +7           00:13:05    00:13:15     11.0

where limit is based on the reference star magnitudo in V filter.