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arXiv · 1307.3032

Do we see accreting magnetars in X-ray pulsars?

K. A. Postnov·N. I. Shakura·A. Yu. Kochetkova·L. Hjalmarsdotter
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Abstract

Strong magnetic field of accreting neutron stars ($10^{14}$ G) is hard to probe by X-ray spectroscopy but can be indirectly inferred from spin-up/spin-down measurement in X-ray pulsars. The existing observations of slowly rotating X-ray pulsars are discussed. It is shown that magnetic fields of neutron stars derived from these observations (or lower limits in some cases) fall within the standard $10^{12}$-$10^{13}$ G range. Claims about the evidence for accreting magnetars are critically discussed in the light of recent progress in understanding of accretion onto slowly rotating neutron stars in the subsonic regime.

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K. A. Postnov, N. I. Shakura, A. Yu. Kochetkova, L. Hjalmarsdotter. 2013-07-11. Do we see accreting magnetars in X-ray pulsars?. https://doi.org/10.1051/epjconf%2F20136402002

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