TITLE:   GCN CIRCULAR
NUMBER:  15556
SUBJECT: GRB 131128A: Bassano Bresciano Observatory optical upper limit
DATE:    13/12/01 15:34:26 GMT
FROM:    Ulisse Quadri at Bassano Bresciano Obs  <oabb@ulisse.bs.it>

U.Quadri, L.Strabla and R.Girelli report:

We imaged the field of GRB 131128A detected 
by SWIFT(trigger 579683) with the robotic 
telescope of (IAU station 565) Bassano Bresciano 
Observatory, Italy (member of ISSP:Italian 
Supernovae Search Project)

The observations started 1h 28m after the                 
GRB trigger at the end of the twilight
with our schmidt telescope 
D=320/400 mm F/D=3.1.

Weather conditions were good.

We co-added 6 series of 10 exposures of 120 sec each.

We did not found any optical counterpart 
in the error box of the XRTcandidate
(E.Sonbas et al. GCNC 15533).

Start      End       Vlim
88min     279min     19.3                                   

The afterglow probably results absorbed in the light of 
the near star USNO-B 2766-00858-1 (R2 = 11.63 mag)   
due to the focal lenght very short (1000mm) of our 
Schmidt telescope.

Magnitudes were estimated with the USNO-B1 cat. 
and are not corrected for galactic dust extinction.

The images are available at:
http://www.osservatoriobassano.org/GRB.asp

The message may be cited.