TITLE: GCN CIRCULAR NUMBER: 21814 SUBJECT: LIGO/VIRGO G298048: Radio detection of SSS17a at 3GHz with the VLA/JAGWAR DATE: 17/09/04 22:14:55 GMT FROM: Kunal Mooley at U of Oxford [8] K. P. Mooley (Hintze Fellow, Oxford), G. Hallinan (Caltech) and A. Corsi (TTU) report on behalf of the JAGWAR and GROWTH teams We observed the location of SSS17a in S band (2-4 GHz) as part of the Jansky Array mapping of GW bursts as Afterglows in Radio (JAGWAR) program on 01-02 Sep 2017 for 5 hours. We report the detection of a source with a signal-to-noise ratio of ~5, consistent within the astrometric uncertainty of the optical transient (Coulter et al. 2017, LVC GCN 21529). We have confirmed this source through comparison with contemporaneous C band observations reported by Corsi et al. (see companion LVC GCN). Multifrequency monitoring of this source with the VLA and other radio facilities has been initiated. We thank the VLA staff for scheduling these observations.