Neutron star mergers as the astrophysical site of the r-process in the Milky Way and its satellite galaxies

Understand

Recent progress of nucleosynthesis work as well as the discovery of a kilonova associated with the gravitational-wave source GW170817 indicates that neutron star mergers (NSM) can be a site of the r-process.

• Several studies of galactic chemical evolution, however, have pointed out inconsistencies between this idea and the observed stellar abundance signatures in the Milky Way: (a) the presence of Eu at low (halo) metallicity and (b) the descending trend of Eu/Fe at high (disc) metallicity.
• In this study, we explore the galactic chemical evolution of the Milky Way's halo, disc and satellite dwarf galaxies.
• Particular attention is payed to the forms of delay-time distributions for both type Ia supernovae (SN Ia) and NSMs.