Formation of double neutron stars and implications for heavy element production

TYPEAstrophysics Seminar
Speaker:Paz Beniamini
Affiliation:IAP
Date:24.11.2016
Time:11:00 - 12:00
Location:
Abstract:Observations of DNS systems in our Galaxy suggest that the formation of the second born NS in most systems involves a very weak explosion, rather than a more "traditional" SNe. This allows us to estimate the typical center of mass velocities and time until merger for double neutron star systems. We find that more than half of the systems are slow enough and merge rapidly enough to be able to account even for the recent observations of r-process elements in ultra-faint dwarf galaxies. Furthermore, observations of the Eu abundances in dwarf galaxies lead to model independent estimates of the rate and mass per event of r-process formation. These suggest rates between 2*10^(-4) and 10^(-3) per ccSNe and Eu masses between 3*10^(-5)M_sun and 2*10^(-4)M_sun. Both values are consistent with expectations for the DNS merger hypothesis.