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GCN Circular 22216

GRB 171205A: VLA detection
2017-12-09T18:19:01Z (6 years ago)
Tanmoy Laskar at UC Berkeley <>
T. Laskar (NRAO / UC Berkeley), D. L. Coppejans, R. Margutti (Northwestern
University), and K. D. Alexander (Harvard) report on behalf of a larger

"The VLA observed GRB 171205A (D'Elia et al.; GCN 22177) at multiple
frequencies from 4.49 GHz to 16.38 GHz beginning on 2017 December 9.58 UT
(4.3 days after the burst). At a mean frequency of 6 GHz, we detect a radio
source with a preliminary flux density of ~ 3 mJy at

RA = 11:09:39.5182 +/- 0.0001
Dec = -12:35:18.480 +/- 0.002

consistent with the Swift/XRT position (Osborne et al.; GCN 22179) and the
optical position (Izzo et al.; GCN 222180, Emery et al.; GCN 22181). The
spectral index is steeply rising to higher frequencies as nu^2, suggesting
a self-absorbed spectrum. Follow-up observations are planned. We thank the
VLA staff for rapidly scheduling and executing these service observations."
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