A transient powered by the radioactive decay of r-process elements the so-called kilonova is one of the possible observational consequences of compact binary mergers including at least one neutron star. Recent observations discover a kilonova associated with the short GRB130603B.
We explore the possible progenitor of this event based on numerical-relativity simulations and radiative transfer simulations for the dynamical ejecta of binary neutron star (NS-NS) mergers and black hole – neutron star binary (BH-NS) mergers. We show that the only soft EOS models could produce the observed luminosity for the NS-NS ejecta. Our results also show that a BH-NS model is more favorable for GRB130603B than a NS-NS model.