2019MNRAS.482.3415I

We use the Bayesian approach to write the posterior probability density for the three-dimensional velocity of a pulsar and for its kinematic age. As a prior, we use the bimodal velocity distribution found in a recent article by Verbunt, Igoshev & Cator. When we compare the kinematic ages with spin-down ages we find that in general they agree with each other. In particular, maximum likelihood analysis sets the lower limit for the exponential magnetic field decay time-scale at 8 Myr with slight preference of t_dec ≃ 12 Myr and compatible with no decay at all. One of the objects in the study, pulsar B0950+08 has kinematic and cooling ages ≃2 Myr which is in strong contradiction with its spin-down age τ ≃ 17 Myr. The 68 per cent credible range for the kinematic age is 1.2-8.0 Myr. We conclude that the most probable explanation for this contradiction is a combination of magnetic field decay and long initial period. Further timing, UV and X-ray observations of B0950+08 are required to better constrain its origin and evolution.