GCN Circular 22258
Subject
GRB 171205A: RATAN observations
Date
2017-12-16T15:59:25Z (6 years ago)
From
Sergei Trushkin at Special Astrophys. Obs.,Russia <sergei.trushkin@gmail.com>
S.A. Trushkin, A.K. Erkenov, P.G. Tsybulev and N.A. Nizhelskij (SAO RAS)
report:
We have observed GRB 171205A (D'Elia et al.; GCN Circ. 22177) with
the RATAN-600 radio telescope at 4.7 and 8.2 GHz from December 9 to
December 16 2017 daily. We have detected a radio fluxes within the RA
errors of the source detected with VLA (Laskar et al.; GCN Circ. 22216).
The mean flux densities are equal 15 +- 2 and 19 +- 2 mJy at 4.7 and 8.2
GHz respectively. But we must notice that there is a known NVSS source
J110939.0-123330 (32 mJy at 1.4 GHz), also detected in the
GLEAM multi-frequency survey: J110938-123334 in the field of GRB 171205A
(J110939.5-123518).
We have probably detected contributions from both sources with the
RATAN arcmin-beams. Thus if we subtract the fluxes from the
NVSS source, using the power-law fitting of its spectrum
we can estimate the refined fluxes from GRB 171205A: < 3 mJy at 4.7 GHz
and 10 +- 3 mJy at 8.2 GHz for mean epoch: December 12 (MJD 58099.0),
i.e. ~7.3 days after the burst.
[GCN OPS NOTE(16dec17): Per GCN, the extra, submitter-supplied 5-line
title-block was removed.]