[vsnet-grb-info 18572] GRB 161007A: NOT optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20020
SUBJECT: GRB 161007A: NOT optical observations
DATE:    16/10/10 10:47:07 GMT
FROM:    Kasper Elm Heintz at Cen.for Astrophys Cosmo/Dark Cosmology Cen  <heintz at dark-cosmology.dk>

K. E. Heintz (Univ. of Iceland and DARK/NBI), D. Malesani (DARK/NBI and DTU Space), A. de Ugarte Postigo (IAA-CSIC and DARK/NBI), T. Pursimo (NOT), T. Kruehler (MPE Garching), J. Telting (NOT) and J. P. U. Fynbo (DARK/NBI) report on behalf of a larger collaboration:

We observed the field of GRB 161007A (D'Elia et al., GCN 20008) using the ALFOSC camera mounted at the 2.56m Nordic Optical Telescope (NOT). Observations started at 04:39:59 UT on 2016-10-09 (i.e., 31 hr after the trigger) and 6x300 s SDSS i-band frames were obtained under excellent seeing (0.6-0.7").

In our stacked i-band image, we clearly detect the object reported by de Ugarte Postigo et al. (GCN 20014). We confirm that this source is extended.

No significant variability is measured with respect to the GTC images (taken 5.3 hr after the GRB) down to ~0.2 mag. The extension, the lack of variability, and the low chance probability association for such a bright object all indicate that this is the host galaxy of GRB 161007A.