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Correlation between X-ray Lightcurve Shape and Radio Arrival Time in the Vela Pulsar

A. 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 emission and radio arrival times on a pulse by pulse basis. At a confidence level of 99.8% we have 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. Our results suggest that the mechanism producing the radio pulses is intimately connected to the mechanism producing X-rays. Current models using resonant absorption of radio emission in the outer magnetosphere as a cause of the X-ray emission are explored as a possible explanation for the correlation.

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A. Lommen, J. Donovan, C. Gwinn, Z. Arzoumanian, A. Harding, M. Strickman, R. Dodson, P. McCulloch, D. Moffett. 2006-11-14. Correlation between X-ray Lightcurve Shape and Radio Arrival Time in the Vela Pulsar. https://doi.org/10.1086/510797

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