[vsnet-grb-info 5799] GRB 080319B: TORTORA synchronous observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  7452
SUBJECT: GRB 080319B: TORTORA synchronous observation
DATE:    08/03/19 17:33:14 GMT
FROM:    Sergey Karpov at SAO RAS  <karpov at sao.ru>

S. Karpov, G. Beskin, S. Bondar, C. Bartolini, G. Greco, A. Guarnieri,
D. Nanni, A. Piccioni, F. Terra, E. Molinari, G. Chincarini, F.M. Zerbi,
S. Covino, V. Testa, G. Tosti, F. Vitali, L.A. Antonelli, P. Conconi, G.
Cutispoto, G. Malaspina, L. Nicastro, E. Palazzi, E. Meurs, P.  Goldoni

report on behalf of the TORTOREM team:

TORTORA wide-field optical camera (12 cm diameter, 20x25 deg FOV, TV-CCD,
unfiltered) mounted on REM robotic 60-cm telescope located at La Silla
(Chile) observed the field of GRB 080319B (GCN 7427, Racusin et al.)
before, during and after the gamma-emission with 0.13 s time resolution.

We observe optical emission at the position given by Swift XRT:

1. We did not detect any transient  brighter than 8.5m (unfiltered,
near B) at T-100 - T+16 s 

2. We detect rapidly rising OT (~5 second rise front) and observe it
between T+16 and T+30, the peak brightness has been around 5 m

3. Between T+30 and T+36 the observations have been paused due to
repointing of REM telescope

4. Since T+36 we continuously observe the transient until it faded below
the detection limit (~8.5m) at T+90 s

The detailed analysis is in progress.

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