![]() In MAD simulations, the 230 GHz emission is nearly equatorial and extends to the black hole event horizon. In Chael+ 2021, I used my simulation images to examine the role of the ``inner shadow’’ in black hole images. As the frequency increases, the brightest emission moves down the jet closer and closer to the black hole.Ģ30 GHz images from my MAD simulations of M87 using damped turbulence (left) and magnetic reconnection (right) to heat electrons Images of of the M87 jet at different frequencies from one of my MAD simulations (Chael+ 2018b). In 2021, I was a co-coordinator of the paper EHT’s first polarimetric images of M87 we found that EHT polarimetric observations also strongly favor a magnetically arrested accretion flow. In Chael+ 2019, I applied the same method to M87’s jet and determined that the observed characteristics are well explained by a Magnetically Arrested Disc model, where extreme magnetic fields on the black hole choke accretion. In Chael+ 2018a I tested two physical mechanisms for electron heating in plasmas – turbulence and magnetic reconnection – to investigate how plasma microphysics changes the images and variability of Sgr A* at different frequencies. This method allows us to directly predict what the Event Horizon Telescope will see and how different models emit across the entire electromagnetic spectrum. In my research, I use the massively parallel code KORAL which moves beyond standard single-fluid GRMHD to a three-fluid approximation where electrons, ions, and photons exchange energy self-consistently. Images of Sgr A* from my simulations (Chael+ 2018a) with four different values of black hole spin and electron heating functions, as viewed by the EHT at 230 GHz. This makes predictions for the images observed by the Event Horizon Telescope difficult. Since most simulations assume thermodynamic equilibrium it is impossible to directly predict the radiation emitted from most simulations without making additional assumptions in post-processing. Unfortunately, in the hot, weakly coupled plasmas around M87 and Sgr A*, protons and electrons are not in thermal equilibrium with each other. ![]()
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