[vsnet-grb-info 17520] GRB 160127A: RATIR Optical Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18950
SUBJECT: GRB 160127A: RATIR Optical Observations
DATE:    16/01/29 16:56:34 GMT
FROM:    Alan M. Watson at Instituto de Astronomia UNAM  <alan at 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
(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 160127A (Amaral-Rogers et al., GCN Circular
18938) 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 2016/01 29.43 to
2016/01 29.55 UTC (49.72 to 52.43 hours after the BAT trigger),
obtaining a total of 1.48 hours exposure in the r, i, and z bands.

We no longer detect the optical counterpart reported by Amaral-Rogers et
al. (GCN Circular 18938), Klotz et al. (GCN Circular 18939), Cucchiara
et al. (GCN Circular 18941), and Siegel et al. (GCN Circular 18945). In
comparison with the SDSS DR9 catalog, we obtain the following 3-sigma
upper limits:

 r	> 23.15
 i	> 23.09
 z	> 20.00

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

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