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A periodically active pulsar giving insight into magnetospheric physics

M. Kramer·A. G. Lyne·J. T. O'Brien·C. A. Jordan·D. R. Lorimer
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Abstract

PSR B1931+24 (J1933+2421) behaves as an ordinary isolated radio pulsar during active phases that are 5-10 days long. However, the radio emission switches off in less than 10 seconds and remains undetectable for the next 25-35 days, then it switches on again. This pattern repeats quasi-periodically. The origin of this behaviour is unclear. Even more remarkably, the pulsar rotation slows down 50% faster when it is on than when it is off. This indicates a massive increase in magnetospheric currents when the pulsar switches on, proving that pulsar wind plays a substantial role in pulsar spin-down. This allows us, for the first time, to estimate the currents in a pulsar magnetospheric during the occurrence of radio emission.

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M. Kramer, A. G. Lyne, J. T. O'Brien, C. A. Jordan, D. R. Lorimer. 2006-04-28. A periodically active pulsar giving insight into magnetospheric physics. https://doi.org/10.1126/science.1124060

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