Mon. Not. R. Astron. Soc., 430, 2281-2301 (2013/April-2)
Pulsar spin-velocity alignment: kinematic ages, birth periods and braking indices.
NOUTSOS A., SCHNITZELER D.H.F.M., KEANE E.F., KRAMER M. and JOHNSTON S.
Abstract (from CDS):
This paper presents a detailed investigation of the dependence of pulsar spin-velocity alignment, which has been observed for a sample of 58 pulsars, on pulsar age. At first, our study considers only pulsar characteristic ages, resulting in no change in the degree of correlation as a function of age, up to at least 100Myr. Subsequently, we consider a more reliable estimate of pulsar age, the kinematic age, assuming that pulsars are born near the Galactic plane. We derive kinematic ages for 52 pulsars, based on the measured pulsar proper motions and positions, by modelling the trajectory of the pulsars in a Galactic potential. The sample of 52 pulsar kinematic ages constitutes the largest number of independently estimated pulsar ages to date. Using only the 33 most reliable kinematic ages from our simulations, we revisit the evolution of spin-velocity alignment, this time as a function of kinematic age. We find that the strong correlation seen in young pulsars is completely smeared out for pulsars with kinematic ages above 10Myr, a length of time beyond which we expect the gravitational pull of the Galaxy to have a significant effect on the directions of pulsar velocities. In the discussion, we investigate the impact of large distance uncertainties on the reliability of the calculated kinematic ages. Furthermore, we present a detailed investigation of the implications of our revised pulsar ages for the braking index and birth-period distributions. Finally, we discuss the predictions of various SN-kick mechanisms and their compatibility with our results.
© 2013 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society (2013)
methods: numerical - pulsars: general - Galaxy: kinematics and dynamics
PSR J1453+6413 (p.2297) is a misprint for PSR J1453-6413, PSR J1932+3252 (p.2284) is a misprint for PSR J1952+3252 and PSR B0538+2817 (p.2284) is a misprint for PSR J0538+2817.
View the reference in ADS
To bookmark this query, right click on this link: simbad:2013MNRAS.430.2281N and select 'bookmark this link' or equivalent in the popup menu