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arXiv · 1401.0772

Rotational Behaviors and Magnetic Field Evolution of Radio Pulsars

Yi Xie·Shuang-Nan Zhang
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Abstract

The observed long-term spin-down evolution of isolated radio pulsars cannot be explained by the standard magnetic dipole radiation with a constant braking torque. However how and why the torque varies still remains controversial, which is an outstanding problem in our understanding of neutron stars. We have constructed a phenomenological model of the evolution of surface magnetic fields of pulsars, which contains a long-term decay modulated by short-term oscillations; a pulsar's spin is thus modified by its magnetic field evolution. The predictions of this model agree with the precisely measured spin evolutions of several individual pulsars; the derived parameters suggest that the Hall drift and Hall waves in the NS crusts are probably responsible for the long-term change and short-term quasi-periodical oscillations, respectively. Many statistical properties of the timing noise of pulsars can be well re-produced with this model, including correlations and the distributions of the observed braking indices of the pulsars, which span over a range of more than 100 millions. We have also presented a phenomenological model for the recovery processes of classical and slow glitches, which can successfully model the observed slow and classical glitch events without biases.

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Yi Xie, Shuang-Nan Zhang. 2014-01-04. Rotational Behaviors and Magnetic Field Evolution of Radio Pulsars. https://doi.org/10.1002/asna.201412108

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