TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  2677
SUBJECT: GRB040825A: optical limit before GRB
DATE:    04/08/27 20:02:21 GMT
FROM:    Grzegorz Wrochna at Soltan Inst.for Nuclear Studies  <wrochna@fuw.edu.pl>

M.Cwiok, L.Mankiewicz, K.Nawrocki, B.Pilecki, L.W.Piotrowski,
G.Pojmanski, R.Salanski, M.Sokolowski, D.Szczygiel, G.Wrochna,
on behalf of "Pi of the Sky / ASAS" collaboration

The central part of HETE FOV containing GRB040825A error box
was observed by "Pi of the Sky" apparatus (http://grb.fuw.edu.pl)
at Las Campanas Observatory for the night of 2004.08.25
from 2:24 UT (1 h 6 min before the GRB)
till 9:35 UT (6 h 4 min after the GRB).

10s exposures were taken continuously with 4s intervals
by two CCD cameras. The single frame limiting magnitude
was strongly varying, due to thin clouds covering the sky.
No OT and no unknown objects have been observed within
the GRB040825A error box.

Preliminary limits for frames PRECEDING, CONTAINING and following
the GRB are 10m, 10m, and 9.5m respectively.

We are working on better limits for integrated frames.
More details can be found at
http://grb.fuw.edu.pl/pi/ot/grb040825a/
-- 
  _____________________________________________________
|                                                     |
| dr hab. Grzegorz Wrochna     http://cern.ch/wrochna |
| Soltan Institute for Nuclear Studies                |
| Hoza 69                  e-mail: wrochna@fuw.edu.pl |
| PL 00-681 Warsaw              tel: +48 22 628 18 93 |
| Poland                        fax: +48 22 621 28 04 |
|_____________________________________________________|