TITLE:   GCN CIRCULAR
NUMBER:  20266
SUBJECT: GRB 161214B: RATIR Optical and Near-Infrared Observations
DATE:    16/12/15 05:21:07 GMT
FROM:    Alan M. Watson at Instituto de Astronomia UNAM  <alan@astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),
William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),
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 161214B (D'Avanzo et al., GCN Circ. 20257)
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 2016/12 15.08 to
2016/12 15.10 UTC (8.60 to 9.05 hours after the BAT trigger), obtaining
a total of 0.26 hours exposure in the r and i bands and 0.15 hours
exposure in the Z, Y, J, and H bands.

We detect a source within the Swift-XRT enhanced error circle (Evans,
GCN Circ 20259. In comparison with the SDSS DR9 and 2MASS catalogs, we
obtain the following magnitudes:

  r	18.87 +/- 0.01
  i	18.56 +/- 0.01
  Z	18.34 +/- 0.01
  Y	18.23 +/- 0.03
  J	18.23 +/- 0.03
  H	18.05 +/- 0.04

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

The fading from r = 18.35 reported at 2.2 hours by Malesani et al. (GCN
Circ. 20260) to our observation of r = 18.87 at 8.8 hours confirms the
behavior reported by Kugel (GCN Circ. 20262). Our image quality is about
1.7 arcsec FWHM, so we are not able to separate this source from the
nearly coincident r = 19.09 SDSS source J001524.26+072108.5 mentioned by
Malesani et al.

We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.