Timing a millisecond pulsar in a globular cluster

Certain evolutionary scenarios predict that millisecond pulsars should form in the cores of globular clusters; such a source may be present in M28. Gravitational perturbations of the cluster stars should subject the pulsar to a time-varying acceleration. This may be detectable in the arrival time analysis as an anomalous spin period much larger than that expected from magnetic dipole braking. This effect can be used as a probe of the cluster dynamics and will degrade the usefulness of such pulsars in searches for long-wavelength cosmological gravitational radiation. (author)