GCN Circular 16175
D. Harbeck (WIYN Observatory), A. Kaur (Clemson U.), A. Delgado-Navarro (Clemson U.), M. Orio (INAF, UW Madison), D. H. Hartmann (Clemson U.) report: We re-imaged the location of the Swift detected GRB 140423A (Sonbas et al., GCN 16142) with the pODI instrument on the 3.5 m WIYN telescope at KPNO ( http://www.wiyn.org/ODI/About/wiynpODI.html). Observations in the sdss r' band on 25 April 2014 consisted of one 300s exposure, and one 600s exposures. The optical counterpart of the burst (Elenin et al., GCN 16143; Kaur et al., GCN 16144; Ferrante et al., GCN 16145; Chester et al., GCN 16147) was detected under good conditions. OBS DATE [UTC at start] T_Exp r' AB stat-error seeing 2014-04-25 07:17:45.434 300.0 22.58 0.1 0.7" 2014-04-25 07:24:59.654 600.0 22.64 0.08 0.75" Calibration was the same as described in our previous report. Calibration rms without color correction is < 0.1", consistency check with nearby SDSS star shows calibration variations < 0.02 mag. No color / foreground extinction correction was applied.