Superhumps, Magnetic Fields and the Mass-ratio in AM Canum Venaticorum
نویسنده
چکیده
We show that the observed K velocities and periodicities of AM CVn can be reconciled given a mass ratio q ≈ 0.22 and a secondary star with a modest magnetic field of surface strength B ∼ 1 T. 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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