Optisk modpart til gammaglimt GRB160131A

SUBJECT: GRB 160131A: RATIR Optical Observations
DATE:    16/01/31 13:36:58 GMT
FROM:    Alan M. Watson at Instituto de Astronomia UNAM
We detect a bright uncatalogued source at 05:12:40.33 -07:03:00
(J2000, ±0.5 arcsec). In comparison with the USNO-B1 catalog,
we obtain the following mean magnitudes:

 r	= 13.35 ± 0.04
 i	= 13.01 ± 0.02
 z	= 12.67 ± 0.04

These magnitudes are in the AB system and are not corrected for
Galactic extinction in the direction of the GRB.
The source fades roughly as t^-0.87 during our observations.
This source is presumably the optical counterpart reported by
Page et al. (GCN Circular 18951), Yurkov et al.
(GCN Circular 18952), Guidorzi et al. (GCN Circular 18953),
and Xin et al. (GCN Circular 18954).
SUBJECT: GRB 160131A: GTC spectroscopy of the afterglow
DATE:    16/01/31 23:49:42 GMT
FROM:    Antonio de Ugarte Postigo at IAA-CSIC
In spite of the poor seeing we detect a strong continuum
across the complete range with multiple absorption
features of FeII, NiII, MnII, MgII, MgI, and CaII at a
common redshift of 0.972, consistent with the value
measured by Malesani et al. from TNG (GCN 18965).