[vsnet-grb-info 18596] GRB161014A: NOT optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20044
SUBJECT: GRB161014A: NOT optical observations 
DATE:    16/10/15 00:35:17 GMT
FROM:    Kasper Elm Heintz at Univ. of Iceland and DARK/NBI  <heintz at dark-cosmology.dk>

K. E. Heintz (Univ. of Iceland and DARK/NBI), D. Xu (NAOC), D. Malesani (DARK/NBI and DTU Space), E. Poretti (INAF/OABr), J. Telting (NOT), A. de Ugarte Postigo (IAA-CSIC and DARK/NBI) and J. P. U. Fynbo (DARK/NBI) report on behalf of a larger collaboration:

We observed the field of GRB 161014A (Racusin et al., GCN 20035) using the ALFOSC camera mounted at the 2.56m Nordic Optical Telescope (NOT). Observations started at 21:22:59 UT on 2016-10-14 (i.e., 8.85 hr after the trigger) and SDSS g-/r-/i-filter frames were obtained with 4x300 s in each filter in a cloudy weather.

In the stacked r- and i-bands we clearly detect the optical afterglow of the burst (Morita et al., GCN 20036, Guidorzi et al., GCN 20037, Xin et al., GCN 20038, Nakaoka et al., GCN 20039 and Mazaeva et al., GCN 20042).

We measure a magnitude of m(r) = 21.60 +/- 0.06 AB mag at a median time of 9.44 hr post-burst, calibrated with nearby SDSS stars.