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GCN Circular 22215

GRB 171205A: UKIRT near-IR observations
2017-12-09T18:18:33Z (6 years ago)
Tanmoy Laskar at UC Berkeley <>
T. Laskar (NRAO / UC Berkeley), W.Fong (Northwestern University), P. Milne,
and N. Smith (University of Arizona) report:

"We observed GRB 171205A (D'Elia et al., GCN 22177) with the Wide Field
Camera (WFCAM) mounted on the 3.8-m United Kingdom Infrared Telescope
(UKIRT) on Mauna Kea beginning on 2017 December 8.595 UT (3.29 days
post-burst) in the J- and K-bands. Using the quick-look pipeline ORAC-DR,
we clearly detect the near-IR counterpart, consistent with the XRT and
optical position (Osborne et al.; GCN 22179, Izzo et al.; GCN 22180, Emery
et al.; GCN 22181). We estimate the following preliminary photometry at the
position of the near-IR afterglow, calibrated to 2MASS and converted to the
AB system:

J(AB) = 18.5 +/- 0.1 mag
K(AB) = 18.3 +/- 0.1 mag

We note that these magnitudes may have a non-negligible contribution from
the host galaxy. Further observations are planned to track the brightness
evolution and determine the galaxy contribution. We thank Watson Varricatt
and Sam Benigni for their assistance in planning and executing these
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