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Correlations between pulsed X-ray flux and radio arrival time in the Vela pulsar

A. N. Lommen·J. Donovan·C. Gwinn·Z. Arzoumanian·A. Harding·M. Strickman·R. Dodson·P. McCulloch·D. Moffett
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Abstract

We report the results of simultaneous observations of the Vela pulsar in X-rays and radio from the RXTE satellite and the Mount Pleasant Radio Observatory in Tasmania. We sought correlations between the Vela's X-ray and radio flux densities and radio arrival times on a pulse by pulse basis. We found significantly higher flux density in Vela's main X-ray peak during radio pulses that arrived early. This excess flux shifts to the 'trough' following the 2nd X-ray peak during radio pulses that arrive later. We suggest that the mechanism producing the radio pulses is intimately connected to the mechanism producing X-rays. Current models using resonant absorption in the outer magnetosphere as a cause of the radio emission, and less directly of the X-ray emission, are explored as a possible explanation for the correlation.

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A. N. Lommen, J. Donovan, C. Gwinn, Z. Arzoumanian, A. Harding, M. Strickman, R. Dodson, P. McCulloch, D. Moffett. 2007-01-04. Correlations between pulsed X-ray flux and radio arrival time in the Vela pulsar. https://arxiv.org/abs/astro-ph/0701103

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