2018/08/31 by Benjamin R. Ryan, Sean M. Ressler, Joshua C. Dolence +3 · 1 citation
Physics and Astronomy · #Accretion (finance) #Active galactic nucleus #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Astrophysics and Star Formation Studies #Dissipation #Electron #Magnetohydrodynamics #Millimeter #Radiative cooling #Radiative transfer #Supermassive black hole #Thin disk #astro-ph.HE
paper · pdf · doi:10.3847/1538-4357/aad73a
17 pages, 8 figures; Fig. 7 corrected, LA-UR number added
openalex created_date 2018/08/22 · openalex publication_date 2018/09/07 · arxiv created 2018/10/18 · arxiv updated 2018/10/22 · openalex updated_date 2026/08/06
Abstract We present axisymmetric two-temperature general relativistic radiation magnetohydrodynamic simulations of the inner region of the accretion flow onto the supermassive black hole M87. We address uncertainties from previous modeling efforts through inclusion of models for (1) self-consistent dissipative and Coulomb electron heating (2) radiation transport (3) frequency-dependent synchrotron emission, self-absorption, and Compton scattering. We adopt a distance D = 16.7 Mpc, an observer angle θ = 20°, and consider black hole masses and spins a ⋆ = (0.5, 0.9375) in a four-simulation suite. For each ( M , a ⋆ ), we identify the accretion rate that recovers the 230 GHz flux from very long baseline interferometry measurements. We report on disk thermodynamics at these accretion rates ( ). The disk remains geometrically thick; cooling does not lead to a thin disk component. While electron heating is dominated by Coulomb rather than dissipation for r ≳ 10 GM / c 2 , the accretion disk remains two-temperature. Radiative cooling of electrons is not negligible, especially for r ≲ 10 GM / c 2 . The Compton y parameter is of order unity. We then compare derived and observed or inferred spectra, millimeter images, and jet powers. Simulations with M / M ⊙ = 3.3 × 10 9 are in conflict with observations. These simulations produce millimeter images that are too small, while the low-spin simulation also overproduces X-rays. For , both simulations agree with constraints on radio/IR/X-ray fluxes and millimeter image sizes. Simulation jet power is a factor 10 2 –10 3 below inferred values, a possible consequence of the modest net magnetic flux in our models.