[vsnet-grb-info 17534] GRB 160131A: Bassano Bresciano Observatory optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18964
SUBJECT: GRB 160131A: Bassano Bresciano Observatory optical observations
DATE:    16/01/31 20:48:03 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 160131A (Page et al., GCN Circular 18951)
with the robotic telescope of (IAU station 565) Bassano Bresciano 
Observatory, Italy (member of ISSP:Italian Supernovae Search Project)

The observations started 9.18 hour after the GRB trigger, at the end of 
twilight, with our Newton telescope D=250 mm F/D=4.8

Initially weather conditions were good, but then the fog has 
forbidden the observations.

We co-added 2 series of 10 exposures of 60 sec each: 
Start T0 + 9.18 hour. End T0+ 9.87 hour  

We clearly detect the optical counterpart (Page et al., GCN 18951; 
Yurkov et al., GCN 18952; Guidorzi et al., GCN 18953;Xin et al.,
GCN 18954; Xin et al., GCN 18955; Watson et al., GCN 18956). 
at the following coordinates:

05h 12m 40.37s -07d 02m 58.9s  +/-2 arcsec

Photometry was performed using comparison stars with UCAC4 catalog.
in CV (clear + Jhonson V) and CR (Clear + Jhonson R) magnitudes, 
and are not corrected for galactic dust extinction:

------------------------------------
      JD         Mag    Filter   SNR
------------------------------------ 
2457419.24025   17.360   CR    14.34 
2457419.26062   17.241   CR     9.74 
                                  
2457419.24025   17.671   CV    14.40 
2457419.26062   17.498   CV     9.74 
-------------------------------------


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

The message may be cited.