GCN Circular 20202
Subject
GRB 161117A: SMARTS optical/IR afterglow observations
Event
Date
2016-11-22T01:11:47Z (9 years ago)
From
Bethany Cobb at GWU <bcobb@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 161117A
(GCN 20179, Cummings et al.) at two epochs (with mid-exposure times of
2016-11-17 02:38 UT & 2016-11-18 01:47 UT). For each epoch, several
dithered images were obtained with total summed exposure times of
15 min in V and I and 12 min in J and K.
The fading afterglow of GRB 161117A (e.g. GCN 20179, Cummings et al.;
GCN 20180, Malesani et al.; GCN 20181, D'Avanzo et al.) was detected
with the following preliminary magnitudes (or 3-sigma limits):
mid-exposure
time post-burst
(hours) V mag I mag J mag K
mag
1.03333 19.42+/-0.10 18.69+/-0.07 18.40+/-0.15 16.49+/-0.11
24.19361 >22.3 >21.1 >18.5 >16.7
(Optical photometry is calibrated against Landolt standard stars
and IR photometry is calibrated against 2MASS stars in the field.)