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arXiv · 0906.4928

Warping modes in discs around accreting neutron stars

H. Meheut·M. Tagger
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Abstract

The origin and stability of a thin sheet of plasma in the magnetosphere of an accreting neutron star is investigated. First the radial extension of such a magnetospheric disc is explored. Then a mechanism for magnetospheric accretion is proposed, reconsidering the bending wave explored by Agapitou, Papaloizou & Terquem (1997), that was found to be stable in ideal MHD. We show that this warping becomes unstable and can reach high amplitudes, in a variant of Pringle's radiation-driven model for the warping of AGN accretion discs (Pringle (1996)). Finally we discuss how this mechanism might give a clue to explain the observed X-ray kHz QPO of neutron star binaries.

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H. Meheut, M. Tagger. 2009-06-26. Warping modes in discs around accreting neutron stars. https://doi.org/10.1111/j.1365-2966.2009.15311.x

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