Kilonova modelling

by Mr Giacomo Ricigliano (Darmstadt U)

Friday 16 Sept 2022, 14:00 → 16:00 Europe/Berlin

HS5 (TPI, FSU Jena)

Matter expelled from binary neutron star (BNS) and black hole-neutron star (BHNS) mergers is one confirmed site capable of harboring r-process nucleosynthesis in the universe, due to its extreme conditions and abundance of neutrons. The freshly produced nuclei are unstable and undergo nuclear decay, releasing an amount of energy sufficient to power a thermal transient known as kilonova (KN). A kilonova shines from a few hours ("blue" KN) to a few weeks ("red" KN) after merger and represents a major electromagnetic counterpart to gravitational wave signals. We start from an analytic solution of the radiative transfer equations to develop a NR informed kilonova model which considers multiple ejecta components, the general anisotropy of their dynamic properties and the projection in the observer viewing direction. The impact of the ejecta composition on the light curves is explored by employing parametrized radioactive heating rates derived from nuclear reaction network calculations and grey opacities obtained with atomic structure calculations. We then take a look at a first model application.