Calibration of neutron star natal kick velocities to isolated pulsar observations

Current prescriptions for supernova natal kicks in rapid binary population synthesis simulations are based on fits of simple functions to single pulsar velocity data. We explore a new parametrization of natal kicks received by neutron stars in isolated and binary systems developed by Mandel & Muller, which is based on 1D models and 3D supernova simulations, and accounts for the physical correlations between progenitor properties, remnant mass, and the kick velocity. We constrain two free parameters in this model using very long baseline interferometry velocity measurements of Galactic single pulsars. We find that the inferred values of natal kick parameters do not differ significantly between single and binary evolution scenarios. The best-fitting values of these parameters are v(ns) = 520 km s(-1) for the scaling prefactor for neutron star kicks, and sigma(ns) = 0.3 for the fractional stochastic scatter in the kick velocities.

Automated summary

Current prescriptions for supernova natal kicks in rapid binary population synthesis simulations are based on fits of simple functions to single pulsar velocity data. We propose a new parametrization of natal kicks received by neutron stars in isolated and binary systems, taking into account physical correlations between progenitor properties, remnant mass, and kick velocity. By constraining free parameters in this model using velocity measurements of Galactic single pulsars, we find that the inferred values of natal kick parameters are similar in single and binary evolution scenarios. The best-fitting values for these parameters are v(ns) = 520 km s(-1) for the scaling prefactor of neutron star kicks, and sigma(ns) = 0.3 for the fractional stochastic scatter in kick velocities.