The Event Horizon General Relativistic Magnetohydrodynamic Code Comparison Project
astro-ph.HE
/ Authors
Oliver Porth, Koushik Chatterjee, Ramesh Narayan, Charles F. Gammie, Yosuke Mizuno, Peter Anninos, John G. Baker, Matteo Bugli, Chi-kwan Chan, Jordy Davelaar
and 18 more authors
Luca Del Zanna, Zachariah B. Etienne, P. Chris Fragile, Bernard J. Kelly, Matthew Liska, Sera Markoff, Jonathan C. McKinney, Bhupendra Mishra, Scott C. Noble, Héctor Olivares, Ben Prather, Luciano Rezzolla, Benjamin R. Ryan, James M. Stone, Niccolò Tomei, Christopher J. White, Ziri Younsi, The Event Horizon Telescope Collaboration
/ Abstract
Recent developments in compact object astrophysics, especially the discovery of merging neutron stars by LIGO, the imaging of the black hole in M87 by the Event Horizon Telescope (EHT) and high precision astrometry of the Galactic Center at close to the event horizon scale by the GRAVITY experiment motivate the development of numerical source models that solve the equations of general relativistic magnetohydrodynamics (GRMHD). Here we compare GRMHD solutions for the evolution of a magnetized accretion flow where turbulence is promoted by the magnetorotational instability from a set of nine GRMHD codes: Athena++, BHAC, Cosmos++, ECHO, H-AMR, iharm3D, HARM-Noble, IllinoisGRMHD and KORAL. Agreement between the codes improves as resolution increases, as measured by a consistently applied, specially developed set of code performance metrics. We conclude that the community of GRMHD codes is mature, capable, and consistent on these test problems.