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arXiv · 1309.4383

Oscillations of the Boundary Layer and High-frequency QPOs

A. A. Blinova·M. Bachetti·M. M. Romanova
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Abstract

We observed persistent high-frequency oscillations of the boundary layer near an accreting, weakly-magnetized star in global 3D MHD simulations. The tilted dipole magnetic field is not strong enough to open a gap between the star and the disk. Instead, it forms a highly-wrapped azimuthal field near the surface of the star which slows down rotation of the disk matter, while a small tilt of the field excites oscillations of the boundary layer with a frequency below the Keplerian frequency. This mechanism may be responsible for the high-frequency oscillations in accreting neutron stars, white dwarfs and classical T Tauri stars.

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A. A. Blinova, M. Bachetti, M. M. Romanova. 2013-09-17. Oscillations of the Boundary Layer and High-frequency QPOs. https://doi.org/10.1051/epjconf%2F20136405009

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