A tidal disruption event coincident with a high-energy neutrino

Cosmic neutrinos provide a unique window into the otherwise hidden mechanism of particle acceleration in astrophysical objects. The IceCube Collaboration recently reported likely association one high-energy neutrino with flare from relativistic jet an active galaxy pointed towards Earth. However combined analysis many similar galaxies revealed no excess broader population, leaving vast majority cosmic flux unexplained. Here we present radio-emitting tidal disruption event, AT2019dsg, second neutrino. AT2019dsg was identified as part our systematic search for optical counterparts to Zwicky Transient Facility. probability finding any coincident event by chance is 0.5%, while bright bolometric energy 0.2%. Our electromagnetic observations can be explained through multizone model, radio revealing central engine, embedded UV photosphere, that powers extended synchrotron-emitting outflow. This provides ideal site petaelectronvolt production. Assuming genuine, suggest events mildly outflows contribute flux. probably associated neutrino, suggesting such emission terms photosphere and