Mass ejection from neutron star mergers: different components and expected radio signals

Understand

In addition to producing a strong gravitational signal, a short gamma-ray burst (GRB), and a compact remnant, neutron star mergers eject significant masses at significant kinetic energies.

• This mass ejection takes place via dynamical mass ejection and a GRB jet but other processes have also been suggested: a shock-breakout material, a cocoon resulting from the interaction of the jet with other ejecta, and viscous and neutrino driven winds from the central remnant or the accretion disk.
• The different components of the ejected masses include up to a few percent of a solar mass, some of which is ejected at relativistic velocities.
• The interaction of these ejecta with the surrounding interstellar medium will produce a long lasting radio flare, in a similar way to GRB afterglows or to radio supernovae.