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Magnetically warped discs in close binaries

James Murray·Dalia Chakrabarty·Graham Wynn·Louisa Kramer
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Abstract

We demonstrate that measurable vertical structure can be excited in the accretion disc of a close binary system by a dipolar magnetic field centred on the secondary star. We present the first high resolution hydrodynamic simulations to show the initial development of a uniform warp in a tidally truncated accretion disc. The warp precesses retrogradely with respect to the inertial frame. The amplitude depends on the phase of the warp with respect to the binary frame. A warped disc is the best available explanation for negative superhumps.

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James Murray, Dalia Chakrabarty, Graham Wynn, Louisa Kramer. 2002-04-30. Magnetically warped discs in close binaries. https://doi.org/10.1046/j.1365-8711.2002.05628.x

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