Global Three Dimensional Relativistic Radiation Magnetohydrodynamics of Magnetically Arrested Disk Accretion Flows in AGNs

Mohammed Ramiz Aktar^1,2*, Kuo-Chuan Pan², Toru Okuda³

¹Institute of Astronomy and Astrophysics, Academia Sinica, Taipei, Taiwan
²Department of Physics and Institute of Astronomy, National Tsing Hua University, Hsinchu, Taiwan
³Hakodate Campus, Hokkaido University of Education, Hakodate, Japan

* Presenter:Mohammed Ramiz Aktar, email:ramizaktar@gmail.com

We conduct three-dimensional radiation-relativistic magnetohydrodynamic (3D Rad-RMHD) simulations of accretion flows around spinning active galactic nuclei (AGNs). Our study focuses on the magnetically arrested disk (MAD) state, using a single-temperature model that incorporates bremsstrahlung opacity as the sole radiation process. We explore a range of black hole spins, from non-spinning to rapidly spinning cases. Our findings indicate that the MAD state persists across all spin values, as evidenced by the normalized magnetic flux at the black hole's horizon and the spatially averaged plasma beta. The overall flow dynamics remain qualitatively similar for all spin models in 3D simulations, suggesting that black hole spin has a minimal effect on the accretion dynamics. Additionally, we perform post-processing with a two-temperature model. This analysis reveals that the electron temperature in the jet region is significantly high, irrespective of the spin. Furthermore, we observe that the temporal evolution of both radiative and synchrotron luminosities behaves similarly across all spin values. Ultimately, our results suggest that black hole spin has a minimal impact on the spectral energy distribution (SED) in accretion flows in the MAD state.

Keywords: Accretion, Black hole physics, Radiative magnetohydrodynamics, Relativistic jets, Supermassive black holes