[vsnet-grb-info 12827] GRB 130131B: VLT/X-shooter acquisition camera limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14174
SUBJECT: GRB 130131B: VLT/X-shooter acquisition camera limits
DATE:    13/02/01 14:16:07 GMT
FROM:    Nial Tanvir at U.Leicester  <nrt3 at star.le.ac.uk>

S. Schulze (PUC, MCSS), Z. Cano (U. Iceland), J. Hjorth, D. Malesani,
J. P. U. Fynbo, D. Xu (DARK/NBI) and N. R. Tanvir (U. Leicester) report 
on behalf of a larger collaboration:

We observed GRB 130131B (Siegel et al., GCN Circ. 14159) with ESO/VLT
X-shooter. Our observation began at 5:49 UT on 1 February, i.e. 10.7 hours
post burst. We imaged the field with the acquisition camera in the r' and z' bands
for 3x100 and 4x100 seconds, respectively.

We found no optical counterpart within the revised Swift/XRT X-ray error circle
reported in Goad et al. (GCN Circ. 14165) down to a limiting magnitudes of 
approximately 23.2 and 22.7 mag in r' and z' band, respectively. These 
measurements are given in the AB system and not corrected for foreground 
extinction.

We thank the ESO staff at Paranal, and in particular Maja Vuckovic and 
Stephane Brillant for quickly performing the observations.