Crab Pulsar Photometry and the Signature of Free Precession

Andrej Cadez; Simon Vidrih; Mirjam Galicic; Alberto Carraminana

doi:10.1051/0004-6361:20000283

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arXiv · astro-ph/0303369

Crab Pulsar Photometry and the Signature of Free Precession

Andrej Cadez·Simon Vidrih·Mirjam Galicic·Alberto Carraminana

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Abstract

Optical photometry for the pulsar PSR0531+21 has been extended with new observations that strengthen evidence for a previously observed 60 seconds periodicity. This period is found to be increasing with time at approximately the same rate as the rotational period of the pulsar. The observed period and its time dependence fit a simple free precession model.

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Andrej Cadez, Simon Vidrih, Mirjam Galicic, Alberto Carraminana. 2003-03-17. Crab Pulsar Photometry and the Signature of Free Precession. https://doi.org/10.1051/0004-6361%3A20000283

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