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10.19.06 MIT Workshop on QPOs Oscillation Modes of the Inner Torus in MHD Simulations of Black-Hole Accretion Disks Collaborators: Omer Blaes (UCSB), Phil Arras (UVa) P. Chris Fragile College of Charleston
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10.19.06 MIT Workshop on QPOs Oscillation Modes of the Inner Torus in MHD Simulations of Black-Hole Accretion Disks I.Hydrodynamic Slender Torus Limit II.MRI Turbulence
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10.19.06 MIT Workshop on QPOs R0R0 Hydrodynamic Slender Torus
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10.19.06 MIT Workshop on QPOs Blaes, Arras, & Fragile (2006) Lowest Order Modes of Slender Torus 3:2 frequency ratio?
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10.19.06 MIT Workshop on QPOs Blaes, Arras, & Fragile (2006) -Abramowicz et al. Lowest Order Modes of Slender Torus
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10.19.06 MIT Workshop on QPOs -Rezzolla et al. Blaes, Arras, & Fragile (2006) Lowest Order Modes of Slender Torus
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10.19.06 MIT Workshop on QPOs Blaes, Arras, & Fragile (2006) Lowest Order Modes of Slender Torus
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10.19.06 MIT Workshop on QPOs 0.998 0 Constant specific angular momentum Vertical Epicyclic & Breathing Mode Blaes, Arras, & Fragile (2006)
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10.19.06 MIT Workshop on QPOs Simulations of Oscillation Modes of Slender Torus Hydrodynamic case –no magnetic fields Initialize 6 lowest order modes at moderate amplitude
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10.19.06 MIT Workshop on QPOs Simulations of Oscillation Modes of Slender Torus All modes appear to be captured by at least one diagnostic Some combination modes are also indicated Blaes, Arras, & Fragile (2006) ||ρ|| 2 δρ V r +V θ
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10.19.06 MIT Workshop on QPOs QPOs in MRI Turbulent Disks (Shearing Box) Hydrodynamic modes in MRI turbulence Arras, Blaes, & Turner (2006) Inertial (g) modes (absent) Acoustic (p) modes
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10.19.06 MIT Workshop on QPOs Global Simulation of MRI Turbulent Disk Does the inner torus display similar mode behavior to the hydrodynamic slender torus? Hawley & Balbus (2002)
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10.19.06 MIT Workshop on QPOs QPOs in MRI Turbulent Disks (Global Simulation) Snapshot of Azimuthally Averaged Density Structure of Inner Torus
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10.19.06 MIT Workshop on QPOs Power Spectrum of Global Simulation Power Spectra of Time Series of Density at Three Points Inside Inner Torus
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10.19.06 MIT Workshop on QPOs Power in Different e im Modes Peaks in density power spectra all correspond to nonaxisymmetric modes m=1 m=2 m=3 m=4
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10.19.06 MIT Workshop on QPOs Snapshot of Density in Equatorial Plane
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10.19.06 MIT Workshop on QPOs Power in Different e im Modes Peaks in density power spectra all correspond to nonaxisymmetric modes Have corotation resonances inside the inner torus. Might be a manifestation of PPI m=1 m=2 m=3 m=4
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10.19.06 MIT Workshop on QPOs Principle PPI Mode Should be Stable
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10.19.06 MIT Workshop on QPOs Final Thoughts… Unclear What This Means for Observed QPO’s in Black Hole X-ray Binaries –Observed QPO’s are not seen in the thermal dominant state, nor are they associated with thermal photons in the other states. –Radial pressure gradients might be significant in the flow structures that are responsible for observed QPO’s. Are there toroidal flow structures in the hard and steep power law states?
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10.19.06 MIT Workshop on QPOs Thermal State Hard State? Steep Power Law State???
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