Bright radio flaring from V404 Cyg detected by AMI-LA
ATel #7658; Kunal Mooley, Rob Fender, Gemma Anderson, Tim Staley (Oxford), Erik Kuulkers (ESAC), Clare Rumsey (Cambridge)
on 18 Jun 2015; 13:22 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Kunal Mooley (kunal.mooley@physics.ox.ac.uk)
Subjects: Radio, X-ray, Request for Observations, Binary, Black Hole, Star, Transient, Variables
Referred to by ATel #: 7659, 7661, 7662, 7663, 7667, 7669, 7671, 7674, 7677, 7681, 7686, 7694, 7701, 7702, 7708, 7720, 7721, 7722, 7726, 7734, 7740, 7959
We report that the X-ray and optical outbursts of the nearby black hole X-ray binary
V404 Cyg / GS 2023+338 (ATels 7646, 7647, 7650) have been accompanied by strong and
highly variable radio emission. AMI-LA, in robotic mode (ALARRM), responded to the
Swift trigger (643949) on June 15, 2015, within two hours and detected a bright (>100 mJy)
and fading radio flare at 16 GHz. Since then, further observations have revealed a
succession of bright radio flares. At face value, the behaviour is reminiscent of the
various timescales of powerful ejection events in GRS 1915+105, and given the
relatively small distance to the source (~2.4 kpc), it is very possible that resolvable
relativistic ejecta are present. Further AMI-LA monitoring is ongoing, and we urge further
observations at all wavelengths to study this outburst.
We would like to thank the AMI team for their responsiveness and hard work in delivering
the data to us. This work is part of the 4 PI SKY project (4pisky.org).
