TITLE:   GCN CIRCULAR
NUMBER:  32228
SUBJECT: GRB 220611A: Continued Gemini Infrared Observations
DATE:    22/06/19 21:39:00 GMT
FROM:    Brendan O'Connor at UMD  <oconnorb@umd.edu>

B. O'Connor (UMD/GWU), E. Troja (U Tor Vergata/ASU), S. Dichiara (PSU),
S. B. Cenko (UMD/GSFC), report on behalf of a larger collaboration:

Additional target of opportunity observations of GRB 220611A
(Cenko et al. GCN 32191) were carried out with the FLAMINGOS-2
spectrograph mounted on the Gemini-South telescope. Observations
began at ~7.7 d in the Ks filter with a total exposure of 912 s.

We detect the GRB afterglow (O’Connor et al. GCNs 32203 and 32217,
Rastinejad et al. GCN 32208, Malesani et al. GCN 32222) with magnitude
Ks~21.8 AB mag calibrated against stars in the 2MASS catalog. Compared
to earlier Ks data (O’Connor et al. GCN 32203, Rastinejad et al. GCN
32208), the infrared counterpart’s temporal decay is consistent with the
decay observed in X-rays by Swift/XRT.

We thank the Gemini staff for rapid scheduling of these observations.