[vsnet-grb-info 18514] GRB 160927A: Bassano Bresciano Observatory optical upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19962
SUBJECT: GRB 160927A: Bassano Bresciano Observatory optical upper limit
DATE:    16/09/28 11:26:02 GMT
FROM:    Ulisse Quadri at Bassano Bresciano Obs  <oabb at ulisse.bs.it>

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

We imaged the field of GRB 160927A detected by SWIFT(trigger 713782)
with the robotic telescope of (IAU station 565) Bassano Bresciano 
Observatory, Italy. Member of: 
AAVSO - American Association of Variable Star Observers.
ISSP - Italian Supernovae Search Project.
UAI/SSV - Unione Astrofili Italiani/sezione stelle variabili.

The observations started 11.72 min after the GRB trigger,  
with our Newton telescope D=250 mm F/D=4.8.

Weather conditions were good.

We co-added 52 exposures of 60 sec each.

Start T0+      End T0+      CV lim
11.72 min     65.71 min     19.5

We did not found any optical counterpart in the error box of the XRTcandidate.
S. L. Gibson (U Leicester), N. Gehrels (NASA/GSFC), et al.

Magnitudes were estimated with the UCAC4 cat. and 
are not corrected for galactic dust extinction.

Reference:
http://www.osservatoriobassano.org/GRB.asp

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