Space velocities of radio pulsars from interstellar scintillations

Scintillation observations are used to determine the space velocities of 71 radio pulsars, including most of the 26 objects with proper motions derived from interferometry. The scintillation velocity is dominated by the peculiar transverse velocity of the neutron star and is insensitive to differential galactic rotation. Velocities have a broad distribution function ranging up to about 150 km/s with a tail extending to about 300 km/s. There is no definitive appearance of a bimodal distribution, however. A correlation of velocity with PP(dot) is confirmed to be a general property of the radio pulsar population. It cannot be explained by any observational selection effect and most plausibly is due to a relationship between a neutron star's magnetic moment and the momentum impulse given to it at or near the time of its formation. A small fraction of the objects are discrepant with respect to the velocity-PP(dot) relation. For some objects, this discrepancy may be evidence for a peculiar evolutionary history. 41 references.