GCN Circular 13567
C. Guidorzi (U. Ferrara), C.G. Mundell, D. Bersier (LJMU), N.R. Tanvir (U. Leicester) report on behalf of a larger collaboration: The 2-m Faulkes Telescope North automatically began observing GRB 120803B (Racusin et al. GCN Circ. 13566) on August 03 2012, 11:09:06 UT corresponding to 180 seconds post burst trigger with BVRi' filters. Within the XRT error circle, in the i-band filter we found the following uncatalogued possibly fading source, R.A. = 20:56:56.46 Dec = +53:18:14.4 (J2000) with an uncertainty of about 1". The detection is marginal, with an estimated magnitude of 19.5 +/- 0.5 in the i band at a mean time of 13.2 minutes (100 s exposure) calibrated against nearby USNOB-1 stars. The source is no longer visible in the latest frames. In the R band we see nothing down to 21.4 mag at 32.5 minutes post burst. The faintness and colour of the source might partially be explained by the relatively large foreground extinction, E(B-V)=1.7.