GCN Circular 15903
J. Elliott (MPE Garching), S. Schmidl (TLS Tautenburg), and J. Greiner (MPE Garching) report on behalf of the GROND team: We observed the field of GRB 140302A (Swift trigger 589685; Pagani et al., GCN #15901) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2m MPG telescope at ESO La Silla Observatory (Chile). Observations started at 08:21:12 UT on the 2nd March 2014, 8.2 min after the GRB trigger. They were performed at an average seeing of 1.5" and at an average airmass of 1.2. We find a faint point source inside the enhanced XRT error circle given in Evans et al. (GCN #15902) RA (J2000.0) = 16:55:26.30 DEC (J2000.0) = -12:52:42.2 with an uncertainty of 0.5" in each coordinate. Based on a total exposure of 1936 sec in r', at a mid-time of 0.65 hrs after the burst, we measure the following preliminary magnitude (in AB): r = 23.7 +/- 0.2 mag. No statement about fading can be made at this stage. Given magnitude is calibrated against GROND zeropoint and is not corrected for the expected Galactic foreground extinction corresponding to a reddening of E_(B-V) = 0.52 mag in the direction of the burst (Schlegel et al. 1998).