[vsnet-grb-info 18168] GRB 160625B: SMARTS optical/IR afterglow observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19616
SUBJECT: GRB 160625B: SMARTS optical/IR afterglow observations
DATE:    16/06/28 20:56:18 GMT
FROM:    Bethany Cobb at GWU  <bcobb at gwu.edu>

B. E. Cobb (GWU) reports:

Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 160625B
(GCN 19580, Dirirsa et al.) with a mid-exposure time of about
32 hours post-burst (2016-06-27 06:51 UT). Total summed exposure
times amounted to 36 minutes in I and 30 minutes in J.

The afterglow of GRB 160625B (e.g. GCN 19585, Melandri et al.;
GCN 19588, Troja et al.; GCN 19589, Oates et al.) is detected
in our images. Preliminary comparison to USNO-B1.0 stars in I
and 2MASS stars in J indicates the following afterglow magnitudes:

mid-exposure
time post-burst       I mag           J mag
1.338 days            18.9+/-0.2      18.6+/-0.1