TY - JOUR
T1 - Large-scale poloidal magnetic field dynamo leads to powerful jets in GRMHD simulations of black hole accretion with toroidal field
AU - Liska, M.
AU - Tchekhovskoy, A.
AU - Quataert, E.
N1 - Funding Information:
We thank P. Bhat and P. Dhang for discussions. This research was enabled by NSF PRAC awards 1615281, OAC-1811605 at the Blue Waters computing project (for the H-AMR simulation) and by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center (for the HARM simulation). ML was supported by the NWO Spinoza Prize (PI M.B.M. van der Klis). This work was supported in part by NSF grant AST-1815304 and NASA grant 80NSSC18K0565 (AT), NSF grants AST 13-33612, AST 1715054, Chandra theory grant TM7-18006X from the Smithsonian Institution, and a Simons Investigator award from the Simons Foundation (EQ).
Publisher Copyright:
© 2020 The Author(s).
PY - 2020
Y1 - 2020
N2 - Accreting black holes (BHs) launch relativistic collimated jets, across many decades in luminosity and mass, suggesting the jet launching mechanism is universal, robust, and scale-free. Theoretical models and general relativistic magnetohydrodynamic (GRMHD) simulations indicate that the key jet-making ingredient is large-scale poloidal magnetic flux. However, its origin is uncertain, and it is unknown if it can be generated in situ or dragged inward from the ambient medium. Here, we use the GPU-accelerated GRMHD code H-AMR to study global 3D BH accretion at unusually high resolutions more typical of local shearing box simulations. We demonstrate that turbulence in a radially extended accretion disc can generate large-scale poloidal magnetic flux in situ, even when starting from a purely toroidal magnetic field. The flux accumulates around the BH till it becomes dynamically important, leads to a magnetically arrested disc (MAD), and launches relativistic jets that are more powerful than the accretion flow. The jet power exceeds that of previous GRMHD toroidal field simulations by a factor of 10 000. The jets do not show significant kink or pinch instabilities, accelerate to γ ∼ 10 over three decades in distance, and follow a collimation profile similar to the observed M87 jet.
AB - Accreting black holes (BHs) launch relativistic collimated jets, across many decades in luminosity and mass, suggesting the jet launching mechanism is universal, robust, and scale-free. Theoretical models and general relativistic magnetohydrodynamic (GRMHD) simulations indicate that the key jet-making ingredient is large-scale poloidal magnetic flux. However, its origin is uncertain, and it is unknown if it can be generated in situ or dragged inward from the ambient medium. Here, we use the GPU-accelerated GRMHD code H-AMR to study global 3D BH accretion at unusually high resolutions more typical of local shearing box simulations. We demonstrate that turbulence in a radially extended accretion disc can generate large-scale poloidal magnetic flux in situ, even when starting from a purely toroidal magnetic field. The flux accumulates around the BH till it becomes dynamically important, leads to a magnetically arrested disc (MAD), and launches relativistic jets that are more powerful than the accretion flow. The jet power exceeds that of previous GRMHD toroidal field simulations by a factor of 10 000. The jets do not show significant kink or pinch instabilities, accelerate to γ ∼ 10 over three decades in distance, and follow a collimation profile similar to the observed M87 jet.
KW - Accretion, accretion discs
KW - Black hole physics
KW - Galaxies: jets
KW - MHD-methods: numerical
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U2 - 10.1093/MNRAS/STAA955
DO - 10.1093/MNRAS/STAA955
M3 - Article
AN - SCOPUS:85085954332
SN - 0035-8711
VL - 494
SP - 3656
EP - 3662
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 3
ER -