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A New HST Measurement of the Crab Pulsar Proper Motion

Patrizia A. Caraveo·Roberto P. Mignani
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Abstract

We have used a set of archived HST/WFPC2 exposures of the inner regions of the Crab Nebula to obtain a new measurement of the pulsar proper motion, the first after the original work of Wyckoff & Murray, more than 20 years ago. Our measurement of the pulsar displacement, mu = 18 +/- 3 mas/yr, agrees well with the value obtained previously. This is noteworthy, since the data we have used span less than 2 years, as opposed to the 77 years required in the previous work. With a position angle of 292 +/- 10 deg, the proper motion vector appears aligned with the axis of symmetry of the inner Crab nebula, as defined by the direction of the X-ray jet observed by ROSAT. Indeed, if the neutron star rotation is to be held responsible both for the X-ray jet and for the observed symmetry, the Crab could provide an example of alignment between spin axis and proper motion.

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Patrizia A. Caraveo, Roberto P. Mignani. 1999-01-05. A New HST Measurement of the Crab Pulsar Proper Motion. https://arxiv.org/abs/astro-ph/9901031

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