TITLE: GCN CIRCULAR NUMBER: 15444 SUBJECT: GRB 131030A: Continued RATIR Optical and NIR Observations DATE: 13/11/04 20:01:34 GMT FROM: Owen Littlejohns at Az State U Owen Littlejohns (ASU), Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (ORAU/GSFC), Eleonora Troja (GSFC), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and Harvey Moseley (GSFC) report: We again observed the field of GRB 131030A (Troja, et al., GCN Circ. 15402) 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 2013/11 4.10 to 2013/11 4.17 UTC (101.35 to 103.16 hours after the BAT trigger), obtaining a total of 1.04 hours exposure in the r and i bands and 0.29 hours exposure in the Z, Y, J, and H bands. We continue to detect the uncatalogued source reported by UVOT (Troja et al., GCN Circ. 15414) in the r, i and Z bands, at fainter magnitudes than the previous epochs of RATIR observations (Littlejohns et al., GCN Circ. 15436; Littlejohns et al., GCN Circ. 15420). For a source within the Swift-XRT error circle, in comparison with the SDSS DR9 and 2MASS, we obtain the following detections and upper limits (3-sigma): r 22.48 +/- 0.13 i 22.71 +/- 0.30 Z 21.70 +/- 0.34 Y > 21.28 J > 21.05 H > 20.49 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. In comparison with the second epoch of RATIR observations the source has faded by an average of 1.8 magnitudes in the r, i and Z bands. The upper limits all indicate that the source has faded by a minimum of approximately 1 magnitude in the Y, J and H bands. Our observations in the Z, Y, J and H bands are consistent with the previously reported power-law decay indices (Littlejohns et al., GCN Circ. 15436), however, there is indication of a steeper decay in both the r and i bands. Between this and the second epoch of RATIR observations we find power-laws of t^-1.33 for the r band and t^-1.72 for the i band. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.