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Proper Motion of the Crab Pulsar Revisited

C. -Y. Ng·Roger W. Romani
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Abstract

It has been suggested that the Crab pulsar's proper motion is well aligned with the symmetry axis of the pulsar wind nebula. We have re-visited this question, examining over 6 years of F547M WFPC2 chip 3 images to obtain a best-fit value of $μ_\ast = 14.9 \pm 0.8$mas/yr at PA $278\arcdeg \pm 3\arcdeg$. At $26\arcdeg\pm 3\arcdeg$ to the nebula axis, this substantially relaxes constraints on the birth kick of this pulsar. Such misalignment allows the momentum to be imparted over $\sim$1s timescales.

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C. -Y. Ng, Roger W. Romani. 2006-02-11. Proper Motion of the Crab Pulsar Revisited. https://doi.org/10.1086/503315

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