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Related papers: Interpreting MAD within multiple accretion regimes

200 papers

We revisit the radiative properties of 3D general relativistic magnetohydrodynamics (GRMHD) two-temperature magnetically arrested disk (MAD) models in which electrons are heated by a magnetic turbulent cascade. We focus on studying the…

High Energy Astrophysical Phenomena · Physics 2025-02-17 M. Moscibrodzka

A widely accepted picture of an accretion flow in the luminous soft spectral state of X-ray binary systems is a geometrically thin disc structure much like the classic analytic solution of Shakura \& Sunyaev. Although the analytic models…

The episodic dynamics of the magnetic eruption of a spinning black hole (BH) accretion disks and its associated intense shapeup of their jets is studied via three-dimensional general-relativistic magnetohydrodynamics (GRMHD). The embedded…

High Energy Astrophysical Phenomena · Physics 2018-07-16 Akira Mizuta , Toshikazu Ebisuzaki , Toshiki Tajima , Shigehiro Nagataki

Wind-fed models offer a unique way to form predictive models of the accretion flow surrounding Sagittarius A*. We present 3D, wind-fed MHD and GRMHD simulations spanning the entire dynamic range of accretion from parsec scales to the event…

High Energy Astrophysical Phenomena · Physics 2023-03-29 Sean M. Ressler , Christopher J. White , Eliot Quataert

The supermassive black hole in the center of the Milky Way, Sgr A*, displays a nearly flat radio spectrum that is typical for jets in active galactic nuclei. Indeed, time-dependent magnetized models of radiatively inefficient accretion…

High Energy Astrophysical Phenomena · Physics 2015-06-17 M. Moscibrodzka , H Falcke

Magnetized accretion flow onto a black hole (BH) may lead to accumulation of poloidal magnetic flux across its horizon, which for high BH spin can power far-reaching relativistic jets. The BH magnetic flux is subject to a saturation…

High Energy Astrophysical Phenomena · Physics 2024-12-04 Krzysztof Nalewajko , Mateusz Kapusta , Agnieszka Janiuk

A selection of results from the general relativistic MHD accretion simulations described in the previous talk are presented. We find that the magnetic field strength increases sharply with decreasing radius and is also enhanced near…

Astrophysics · Physics 2008-11-26 J. H. Krolik , S. Hirose

The magnetically arrested disks (MADs) have attracted much attention in recent years. The formation of MADs are usually attributed to the accumulation of a sufficient amount of dynamically significant poloidal magnetic flux. In this work,…

High Energy Astrophysical Phenomena · Physics 2024-11-28 Jia-Wen Li , Xinwu Cao

We summarize results from a survey of radiation-dominated black hole accretion flows across a wide range of mass accretion rates, as well as two values of black hole spin and initial magnetic field geometry. These models apply an algorithm…

High Energy Astrophysical Phenomena · Physics 2025-09-16 Lizhong Zhang , James M. Stone , Patrick D. Mullen , Shane W. Davis , Yan-Fei Jiang , Christopher J. White

We present two-temperature, radiative general relativistic magnetohydrodynamic simulations of Magnetically Arrested Discs (MAD) that launch powerful relativistic jets. The mass accretion rates of our simulations are scaled to match the…

High Energy Astrophysical Phenomena · Physics 2019-04-11 Andrew Chael , Ramesh Narayan , Michael D. Johnson

Radio galaxies are a subclass of active galactic nuclei that drive relativistic jets from their center and are observed in radio to very-high-energy gamma rays. The emission mechanisms and regions are still unknown. High-energy gamma rays…

High Energy Astrophysical Phenomena · Physics 2024-11-15 Riku Kuze , Shigeo S. Kimura , Kenji Toma

We present global radiation GRMHD simulations of strongly magnetized accretion onto a spinning, stellar mass black hole at sub-Eddington rates. Using a frequency-dependent Monte Carlo procedure for Compton scattering, we self-consistently…

High Energy Astrophysical Phenomena · Physics 2021-10-04 Jason Dexter , Nicolas Scepi , Mitchell C. Begelman

Radiatively inefficient accretion flows (RIAFs) are believed to power supermassive black holes (SMBH) in the underluminous cores of galaxies. Such black holes are typically accompanied by flat-spectrum radio cores indicating the presence of…

High Energy Astrophysical Phenomena · Physics 2014-10-08 Monika Moscibrodzka , Heino Falcke , Hotaka Shiokawa , Charles F. Gammie

We report results from simulations in general relativity of magnetized disks accreting onto merging black hole binaries, starting from relaxed disk initial data. The simulations feature an effective, rapid radiative cooling scheme as a…

Observations are providing increasingly detailed quantitative information about the accretion flows that power such high energy systems as X-ray binaries and active galactic nuclei. Analytic models of such systems must rely on assumptions…

Astrophysics · Physics 2008-11-26 J. F. Hawley , J. -P. De Villiers

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 significant accumulation of magnetic flux around the black hole. This…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Ramesh Narayan , Aleksander Sadowski , Robert F. Penna , Akshay K. Kulkarni

We studied magnetically arrested disks (MAD) around rotating black holes (BH), under the influence of radiative cooling. We introduce a critical value of the mass accretion rate $\dot M_{\rm crit}$ for which the cooling by the synchrotron…

High Energy Astrophysical Phenomena · Physics 2025-02-18 Akshay Singh , Damien Bégué , Asaf Pe'er

We investigate the launching mechanism of relativistic jets from black hole sources, in particular the strong winds from the surrounding accretion disk. Numerical investigations of the disk wind launching - the simulation of the…

High Energy Astrophysical Phenomena · Physics 2018-06-06 Qian Qian , Christian Fendt , Christos Vourellis

We present a comprehensive analysis of four near-Eddington black hole accretion models computed by solving the GRMHD equations with full radiation transport. This study focuses on the dynamical effects of magnetic field topology and black…

High Energy Astrophysical Phenomena · Physics 2026-03-09 Lizhong Zhang , James M. Stone , Shane W. Davis , Yan-Fei Jiang , Patrick D. Mullen , Christopher J. White

The exact time-dependent solution is obtained for a magnetic field growth during a spherically symmetric accretion into a black hole (BH) with a Schwarzschild metric. Magnetic field is increasing with time, changing from the initially…

High Energy Astrophysical Phenomena · Physics 2019-06-03 G. S. Bisnovatyi-Kogan