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GCN Circular 20432

GRB 170111A: SMARTS optical/IR observations
2017-01-11T20:41:35Z (7 years ago)
Bethany Cobb at GWU <>
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 170111A
(GCN 20423, Beardmore et al.) with a mid-exposure time of about
1 hour post-burst (2017-01-11 01:36 UT). Total summed exposure
times amounted to 36 minutes in I and 30 minutes in J.

No source is detected at the position of the X-ray
afterglow (GCN 20424, Evans et al.) in either I or J,
to an approximate 3-sigma limiting magnitude of I > 21.9
(calibrated using USNO-B1.0 stars).
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