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arXiv · 1610.09561

Near-periodical spin period evolution in the binary system LMC X-4

S. Molkov·A. Lutovinov·M. Falanga·S. Tsygankov·E. Bozzo
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Abstract

In this paper we investigated the long-term evolution of the pulse-period in the high-mass X-ray binary LMC X-4 by taking advantage of more than 43~yrs of measurements in the X-ray domain. Our analysis revealed for the first time that the source is displaying near-periodical variations of its spin period on a time scale of roughly 6.8~yrs, making LMC X-4 one of the known binary systems showing remarkable long term spin torque reversals. We discuss different scenarios to interpret the origin of these torque reversals.

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S. Molkov, A. Lutovinov, M. Falanga, S. Tsygankov, E. Bozzo. 2016-10-29. Near-periodical spin period evolution in the binary system LMC X-4. https://doi.org/10.1093/mnras%2Fstw2429

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