Ray-tracing state-of-the-art simulation data enables the H-AMR collaboration to explore the connections between the theory, numerical simulations and observations. More specifically our collaboration makes predictions about the visual appearance of black holes in various frequency bands. To make such images we use the general relativistic ray-tracing (GRRT) codes BHOSS and xTrack to shoot photons directly through H-AMR data. Below you see an example of a ray-traced image of the highest-ever resolution GRMHD simulation (video) relevant to supermassive black hole M87 in radio (230 GHz). The high resolution allows us to quantify the effects of small-scale accretion disk turbulence on the generated images and lightcurves, which would not be possible with other GRMHD codes. This image was made by my collaborator Koushik Chatterjee in BHOSS.
Exploring Black Hole Light Curve Variability
The H-AMR collaboration also quantifies the (spectral) variability in black hole lightcurves using general relativistic ray-tracing (GRRT) . As an example, the ray-traced X-Ray light-curve of a simulation of a highly tilted accretion disk (video) is shown below (made by collaborator Andrew West and Henric Krawvzynski). We find distinct peaks in the power spectrum at 2.5 Hz, 56 Hz, 88Hz and 112 Hz, which is consistent with observed quasi-periodic oscillations (QPOs) observed in black hole lightcurves. These QPOs are caused by precession of the accretion disk and radial epicyclic oscillations seeded at the tearing radius. We plan to publish these results in the 2023 timeframe.
