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arXiv · 0904.0560

1 Hz flaring in SAX J1808.4--3658: flow instabilities near the propeller stage

A. Patruno·A. L. Watts·M. Klein-Wolt·R. Wijnands·M. van der Klis
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Abstract

We present a simultaneous periodic and aperiodic timing study of the accreting millisecond X-ray pulsar SAX J1808.4-3658. We analyze five outbursts of the source and for the first time provide a full and systematic investigation of the enigmatic phenomenon of the 1 Hz flares observed during the final stages of some of the outbursts. We show that links between pulsations and 1 Hz flares might exist, and suggest they are related with hydrodynamic disk instabilities that are triggered close to the disk-magnetosphere boundary layer when the system is entering the propeller regime.

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A. Patruno, A. L. Watts, M. Klein-Wolt, R. Wijnands, M. van der Klis. 2009-04-03. 1 Hz flaring in SAX J1808.4--3658: flow instabilities near the propeller stage. https://doi.org/10.1088/0004-637x/707/2/1296

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