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We study the dynamics of radiation pressure supported tori around Schwarzschild black holes, focusing on their oscillatory response to an external perturbation. Using KORAL, a general relativistic radiation hydrodynamics code capable of modeling all radiative regimes from the optically thick to the optically thin, we monitor a sample of models at different initial temperatures and opacities, evolving them in two spatial dimensions for $sim 165$ orbital periods. The dynamics of models with high opacity is very similar to that of purely hydrodynamics models, and it is characterized by regular oscillations which are visible also in the light curves. As the opacity is decreased, the tori quickly and violently migrate towards the gas-pressure dominated regime, collapsing towards the equatorial plane. When the spectra of the $L_2$ norm of the mass density are considered, high frequency inertial-acoustic modes of oscillations are detected (with the fundamental mode at a frequency $68 M_{rm BH}^{-1},rm Hz$), in close analogy to the phenomenology of purely hydrodynamic models. An additional mode of oscillation, at a frequency $129 M_{rm BH}^{-1},rm Hz$, is also found, which can be unambiguously attributed to the radiation. The spectra extracted from the light curves are typically more noisy, indicating that in a real observation such modes would not be easily detected.
Context. Some microquasars exhibit millisecond quasi-periodic oscillations (QPO) that are likely related to phenomena occuring in the immediate vicinity of the central black hole. Oscillations of accretion tori have been proposed to model these QPOs.
We performed axisymmetric hydrodynamical simulations of oscillating tori orbiting a non-rotating black hole. The tori in equilibrium were constructed with a constant distribution of angular momentum in a pseudo-Newtonian potential (Klu{z}niak-Lee). M
The tidal force from a third body near a binary system could introduce long-term oscillations in the binarys eccentricity, known as Kozai-Lidov oscillations. We show that the Kozai-Lidov oscillations of stellar-mass black hole binaries have the poten
Supermassive black holes are believed to be the central power house of active galactic nuclei. Applying the pulsar outer-magnetospheric particle accelerator theory to black-hole magnetospheres, we demonstrate that an electric field is exerted along t
We report ALMA observations of CO(3-2) emission in a sample of 7 Seyfert/LINER galaxies at the unprecedented spatial resolution of 0.1 = 4-9 pc. Our aim is to explore the close environment of AGN, and the dynamical structures leading to its fueling.