2 research outputs found
A statistical study of 233 pulsar proper motions
We present and analyse a catalogue of 233 pulsars with proper motion
measurements. The sample contains a wide variety of pulsars including recycled
objects and those associated with globular clusters or supernova remnants.
After taking the most precise proper motions for those pulsars for which
multiple measurements are available, the majority of the proper motions (58%)
are derived from pulsar timing methods, 41% using interferometers and the
remaining 1% using optical telescopes. Many of the 1-D and 2-D speeds
(referring to speeds measured in one coordinate only and the magnitudes of the
transverse velocities respectively) derived from these measurements are
somewhat lower than earlier estimates because of the use of the most recent
electron density model in determining pulsar distances. The mean 1-D speeds for
the normal and recycled pulsars are 152(10) and 54(6) km/s respectively. The
corresponding mean 2-D speeds are 246(22) and 87(13) km/s. PSRs B2011+38 and
B2224+64 have the highest inferred 2-D speeds of ~1600 km/s. We study the mean
speeds for different subsamples and find that, in general, they agree with
previous results. Applying a novel deconvolution technique to the sample of 73
pulsars with characteristic ages less than 3 Myr, we find the mean 3-D pulsar
birth velocity to be 400(40) km/s. The distribution of velocities is well
described by a Maxwellian distribution with 1-D rms sigma=265 km/s. There is no
evidence for a bimodal velocity distribution. The proper motions for PSRs
B1830-08 and B2334+61 are consistent with their proposed associations with the
supernova remnants W41 and G114.3+0.3 respectively.Comment: 20 pages, accepted by MNRA