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Frequency Correlations of QPOs Based on a Disk Oscillation Model in Warped Disks

Shoji Kato
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Abstract

In previous papers we proposed a model that high-frequency quasi-periodic oscillations (QPOs) observed in black-hole and neutron-star X-ray binaries are disk oscillations (inertial-acoustic and/or g-mode oscillations) resonantly excited on warped disks. In this paper we examine whether time variations of the QPOs and their frequency correlations observed in neutron-star X-ray binaries can be accounted for by this disk-oscillation model. By assuming that a warp has a time-dependent precession, we can well describe observed frequency correlations among kHz QPOs and LF QPOs in a wide range of frequencies.

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Shoji Kato. 2007-01-04. Frequency Correlations of QPOs Based on a Disk Oscillation Model in Warped Disks. https://doi.org/10.1093/pasj%2F59.2.451

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