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arXiv · 2505.11446

Polarization Signatures of Quasi-Periodic Oscillations in Simulated Tilted, Truncated Disks

Abstract

We utilize the Monte Carlo radiation transport code, Pandurata, to create images, spectra, polarization maps, and light curves from a set of general relativistic magnetohydrodynamic simulations of tilted, truncated, black hole accretion disks. Truncation can have spectral and polarization signatures all its own; tilt introduces both inclination and azimuthal dependencies into the spectra and polarization; and precession and oscillations of the tilted accretion flow inside the truncation radius introduce time dependencies or periodicity to all of this. We use the ray-traced results from our simulations to evaluate the feasibility of measuring these effects, particularly in the context of current and future X-ray polarization observatories. Such detections could greatly improve our understanding of the geometry of accretion disks and coronae in the hard state, the physics of quasi-periodic oscillations (QPOs), and how system properties evolve as sources approach the hard-to-soft state transition.

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P. Chris Fragile, Deepika A. Bollimpalli, Jeremy D. Schnittman, Cesare Harvey. 2025-08-25. Polarization Signatures of Quasi-Periodic Oscillations in Simulated Tilted, Truncated Disks. https://doi.org/10.3847/1538-4357%2Fadfde1

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