[ Previous | Next | ADS ]

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).