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Non-axisymmetric Structure of Accretion Disks in Be/X-ray Binaries

Kimitake Hayasaki·Atsuo T. Okazaki
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Abstract

The non-axisymmetric structure of accretion disks around the neutron star in Be/X-ray binaries is studied by analyzing the results from three dimensional (3D) Smoothed Particle Hydrodynamics (SPH) simulations. It is found that ram pressure due to the phase-dependent mass transfer from the Be-star disk excites a one-armed, trailing spiral structure in the accretion disk around the neutron star. The spiral wave has a transient nature; it is excited around the periastron, when the material is transferred from the Be disk, and is gradually damped afterwards. It is also found that the orbital phase-dependence of the mass-accretion rate is mainly caused by the inward propagation of the spiral wave excited in the accretion disk.

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Kimitake Hayasaki, Atsuo T. Okazaki. 2004-12-09. Non-axisymmetric Structure of Accretion Disks in Be/X-ray Binaries. https://arxiv.org/abs/astro-ph/0412203

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