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Constraining the Accretion Flow in Sgr A* by General Relativistic Dynamical and Polarized Radiative Modeling
Roman V. Shcherbakov, Robert F. Penna, Jonathan C. McKinney
We briefly summarize the method of simulating Sgr A* polarized sub-mm spectra from the accretion flow and fitting the observed spectrum. The dynamical flow model is based on three-…
The Shakura-Sunyaev Viscosity Prescription with Variable alpha(r)
Robert F. Penna, Aleksander Sadowski, Akshay K. Kulkarni +1
Almost all hydrodynamic accretion disk models parametrize viscosity with the dimensionless parameter alpha. There is no detailed model for alpha, so it is usually taken to be a con…
GRMHD Simulations of Magnetized Advection Dominated Accretion on a Non-Spinning Black Hole: Role of Outflows
Ramesh Narayan, Aleksander Sadowski, Robert F. Penna +1
We present results from two long-duration GRMHD simulations of advection-dominated accretion around a non-spinning black hole. The first simulation was designed to avoid significan…
The Eye of the Storm: Light from the Inner Plunging Region of Black Hole Accretion Discs
Yucong Zhu, Shane W. Davis, Ramesh Narayan +3
It is generally thought that the light coming from the inner plunging region of black hole accretion discs contributes negligibly to the disc's overall spectrum, i.e. the plunging…