Revisiting the Galactic Double Neutron Star merger and LIGO detection rates

Understand

We revisit the merger rate for Galactic double neutron star (DNS) systems in light of recent observational insight into the longitudinal and latitudinal beam shape of the relativistic DNS PSR J1906$+$0746.

• Due to its young age and its relativistic orbit, the pulsar contributes significantly to the estimate of the joint Galactic merger rate.
• We follow previous analyses by modelling the underlying pulsar population of nine merging DNS systems and study the impact and resulting uncertainties when replacing simplifying assumptions made in the past with actual knowledge of the beam shape, its extent and the viewing geometry.
• We find that the individual contribution of PSR J1906$+$0746 increases to $R = 6^{+28}_{-5}$ Myr$^{-1}$ although the values is still consistent with previous estimates given the uncertainties.