Pulsar Timing and the Special Theory of Relativity
Year: 1996
Keywords: relativity, pulsar timing, gravitational field
Millisecond pulsar timing algorithms place all measurements into a solar-centered reference frame, which is assumed to be inertial with respect to the Earth, after correcting the Earth's motion to that of a perfectly circular orit in a constant gravitational field. However, this analysis is valid only if the pulsar exhibits no proper motion with respect to solar barycenter. Since this is likely never to be the case, a relativistic correction must be made to account for the Earth's constantly changing velocity with respect to the reference frame of the pulsar source. This correction takes the form of a periodic timing residual, on the order or microseconds, which should be detectable through the use of pulsar timing arrays, low period pulsars with large proper motions. The absence of such a residual may constitute a failure of special relativity.