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arXiv · 1802.02822

The Crab pulsar: ion-proton plasma and high-frequency radio spectrum

P B Jones
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Abstract

Salient features of the remarkable band structure seen in the high-frequency interpulse of the Crab pulsar are summarized. It is argued that its source must lie in a current sheet, probably coincident with the open-closed magnetosphere separatrix, and that the mechanism is a form of one-pass free-electron laser. An outward moving electron component in the current sheet interacts with the longitudinal electric field of an inward directed ion-proton Lamgmuir mode. The band structure is then a natural consequence of the differing charge-to-mass ratios of the ions, which are a return current component of those accelerated, as in almost all pulsars, from the polar cap to the light cylinder.

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P B Jones. 2018-02-08. The Crab pulsar: ion-proton plasma and high-frequency radio spectrum. https://doi.org/10.1093/mnras%2Fsty2107

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