Caltech-NRAO Stripe 82 Survey (CNSS) Paper III: The First Radio-Discovered Tidal Disruption Event, CNSS J0019+00

We present the discovery of a nuclear transient with the Caltech-NRAO Stripe 82 Survey (CNSS), a dedicated radio transient survey carried out with the Karl G. Jansky Very Large Array (VLA). This transient, CNSS J001947.3+003527, exhibited a turn-on over a timescale of ≲1 yr, increasing in flux density at 3 GHz from 500μJy) of about 2×10⁻³deg⁻², or equivalently a volumetric rate of about 10 Gpc⁻³ yr⁻¹. This rate implies that all-sky radio surveys such as the VLA Sky Survey and those planned with ASKAP, will find many tens of radio TDEs over the next few years.