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arXiv · 1412.7292

Simulations of flux variability of oscillating accretion fluid tori around Kerr black holes

Pavel Bakala·Kateřina Goluchová·Eva Šrámková·Andrea Kotrlová·Gabriel Török·Frederic H. Vincent·Marek A. Abramowicz
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Abstract

High frequency quasi-periodic oscillations (HF QPOs) are observed in the X-ray power-density spectra (PDS) of several microquasars and low mass X-ray binaries. Many proposed QPO models are based on oscillations of accretion toroidal fluid structures orbiting in the vicinity of a compact object. We study oscillating accretion tori orbiting in the vicinity of a Kerr black hole. We demonstrate that significant variation of the observed flux can be caused by the combination of radial and vertical oscillation modes of a slender, polytropic, perfect fluid, non-self-graviting torus with constant specific angular momentum. We investigate two combinations of the oscillating modes corresponding to the direct resonance QPO model and the modified relativistic precession QPO model.

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Pavel Bakala, Kateřina Goluchová, Eva Šrámková, Andrea Kotrlová, Gabriel Török, Frederic H. Vincent, Marek A. Abramowicz. 2014-12-23. Simulations of flux variability of oscillating accretion fluid tori around Kerr black holes. https://doi.org/10.1017/s1743921315002525

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