TITLE: GCN CIRCULAR NUMBER: 19196 SUBJECT: GRB 160314A: RATIR Optical and NIR Observations DATE: 16/03/15 20:32:00 GMT FROM: Alan M. Watson at Instituto de Astronomia UNAM Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (GSFC/STScI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report: We observed the field of GRB 160314A (D'Elia et al., GCN Circ. 19182) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2016/03 15.13 to 2016/03 15.36 UTC (15.59 to 21.16 hours after the BAT trigger), obtaining a total of 3.56 hours exposure in the r and i bands and 1.49 hours exposure in the Z, Y, J, and H bands. For a source within the Swift-XRT error circle (Osborne et al., GCN Circ. 19185), in comparison with the SDSS DR9 and 2MASS catalogs, we obtain the following detections and 3-sigma upper limit: r 22.83 +/- 0.10 i 22.37 +/- 0.06 Z 22.27 +/- 0.15 Y 22.40 +/- 0.21 J 21.93 +/- 0.19 H > 22.38 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. Compared to the NOT observations reported by Malesani et al. (GCN Circ. 19191), we detect fading in r at the 3.7-sigma level between mean epochs of 9.2 and 18.4 hours after the bursts. This confirms that the NOT source is the optical counterpart of the GRB. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.