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arXiv · astro-ph/0310422

Superhumps, Magnetic Fields and the Mass-ratio in AM Canum Venaticorum

K. J. Pearson
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Abstract

We show that the observed K-velocities and periodicities of AM CVn can be reconciled given a mass ratio of 0.22 and a secondary star with a modest magnetic field of surface strength of order 1 Tesla. We see that the new mass ratio implies that the secondary is most likely semi-degenerate. The effect of the field on the accretion disc structure is examined. The theory of precessing discs and resonant orbits is generalised to encompass higher order resonances than 3:2 and shown to retain consistency with the new mass ratio.

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K. J. Pearson. 2003-10-15. Superhumps, Magnetic Fields and the Mass-ratio in AM Canum Venaticorum. https://doi.org/10.1046/j.1365-2966.2003.07290.x

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