TY - JOUR
T1 - A Survey of General Relativistic Magnetohydrodynamic Models for Black Hole Accretion Systems
AU - Dhruv, Vedant
AU - Prather, Ben
AU - Wong, George N.
AU - Gammie, Charles F.
N1 - V.D. is grateful to Abhishek Joshi for discussions that greatly improved the quality of certain sections in this text. V.D. was supported in part by the ICASU/NCSA Fellowship. G.N.W. was supported by the Taplin Fellowship and the Princeton Gravity Initiative. This work was supported by NSF grants AST 17-16327 (horizon), OISE 17-43747, and AST 20-34306. This research used resources of the Oak Ridge Leadership Computing Facility at the Oak Ridge National Laboratory, which is supported by the Office of Science of the U.S. Department of Energy under contract No. DE-AC05-00OR22725. This research used resources of the Argonne Leadership Computing Facility, which is a DOE Office of Science User Facility supported under contract DE-AC02-06CH11357. This research is part of the Delta research computing project, which is supported by the National Science Foundation (award OCI 2005572), and the State of Illinois. Delta is a joint effort of the University of Illinois at Urbana-Champaign and its National Center for Supercomputing Applications. The data analysis was possible thanks to the high throughput computing utility \u201CLauncher\u201D (L. A. Wilson 2017). This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant No. ACI-1548562, specifically the XSEDE resources Longhorn, Frontera, and Stampede2 at the Texas Advanced Computing Center (TACC) through allocation TG-AST170024. The authors acknowledge the Texas Advanced Computing Center (TACC) at The University of Texas at Austin for providing computational resources that have contributed to the research results reported within this paper.
PY - 2025/3/1
Y1 - 2025/3/1
N2 - General relativistic magnetohydrodynamics (GRMHD) simulations are an indispensable tool in studying accretion onto compact objects. The Event Horizon Telescope (EHT) frequently uses libraries of ideal GRMHD simulations to interpret polarimetric, event-horizon-scale observations of supermassive black holes at the centers of galaxies. In this work, we present a library of 10 nonradiative, ideal GRMHD simulations that were utilized by the EHT Collaboration in their analysis of Sagittarius A*. The parameter survey explores both low (SANE) and high (MAD) magnetization states across five black hole spins a* = −15/16, −1/2, 0, +1/2, +15/16 where each simulation was run out to 30,000 GM/c−3. We find the angular momentum and energy flux in SANE simulations closely matches the thin-disk value, with minor deviations in prograde models due to fluid forces. This leads to spin equilibrium around a* ∼ 0.94, consistent with previous studies. We study the flow of conserved quantities in our simulations and find mass, angular momentum, and energy transport in SANE accretion flows to be primarily inward and fluid dominated. MAD models produce powerful jets with outflow efficiency >1 for a* = + 0.94, leading to black hole spin-down in prograde cases. We observe outward directed energy and angular momentum fluxes on the horizon, as expected for the Blandford-Znajek mechanism. MAD accretion flows are sub-Keplerian and exhibit greater variability than their SANE counterpart. They are also hotter than SANE disks within r ≲ 10 GM/c−2. This study is accompanied by a public release of simulation data at http://thz.astro.illinois.edu/.
AB - General relativistic magnetohydrodynamics (GRMHD) simulations are an indispensable tool in studying accretion onto compact objects. The Event Horizon Telescope (EHT) frequently uses libraries of ideal GRMHD simulations to interpret polarimetric, event-horizon-scale observations of supermassive black holes at the centers of galaxies. In this work, we present a library of 10 nonradiative, ideal GRMHD simulations that were utilized by the EHT Collaboration in their analysis of Sagittarius A*. The parameter survey explores both low (SANE) and high (MAD) magnetization states across five black hole spins a* = −15/16, −1/2, 0, +1/2, +15/16 where each simulation was run out to 30,000 GM/c−3. We find the angular momentum and energy flux in SANE simulations closely matches the thin-disk value, with minor deviations in prograde models due to fluid forces. This leads to spin equilibrium around a* ∼ 0.94, consistent with previous studies. We study the flow of conserved quantities in our simulations and find mass, angular momentum, and energy transport in SANE accretion flows to be primarily inward and fluid dominated. MAD models produce powerful jets with outflow efficiency >1 for a* = + 0.94, leading to black hole spin-down in prograde cases. We observe outward directed energy and angular momentum fluxes on the horizon, as expected for the Blandford-Znajek mechanism. MAD accretion flows are sub-Keplerian and exhibit greater variability than their SANE counterpart. They are also hotter than SANE disks within r ≲ 10 GM/c−2. This study is accompanied by a public release of simulation data at http://thz.astro.illinois.edu/.
UR - http://www.scopus.com/inward/record.url?scp=85218905188&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85218905188&partnerID=8YFLogxK
U2 - 10.3847/1538-4365/adaea6
DO - 10.3847/1538-4365/adaea6
M3 - Article
AN - SCOPUS:85218905188
SN - 0067-0049
VL - 277
JO - Astrophysical Journal, Supplement Series
JF - Astrophysical Journal, Supplement Series
IS - 1
M1 - 16
ER -