English
Related papers

Related papers: An Extension of the Athena++ Code Framework for Ra…

200 papers

We present a novel solver technique for the anisotropic heat flux equation, aimed at the high level of anisotropy seen in magnetic confinement fusion plasmas. Such problems pose two major challenges: (i) discretization accuracy and (ii)…

Numerical Analysis · Mathematics 2024-03-15 Golo A. Wimmer , Ben S. Southworth , Thomas J. Gregory , Xian-Zhu Tang

HII regions powered by ionizing radiation from massive stars drive the dynamical evolution of the interstellar medium. Fast radiative transfer methods for incorporating photoionization effects are thus essential in astrophysical…

Instrumentation and Methods for Astrophysics · Physics 2025-02-25 Cheryl S. C. Lau , Maya A. Petkova , Ian A. Bonnell

We present a sub-grid model that emulates the magnetic dynamo operating in magnetized accretion disks. We have implemented this model in the general relativisic radiation magnetohydrodynamic (GRRMHD) code \koral, using results from local…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Aleksander Sadowski , Ramesh Narayan , Alexander Tchekhovskoy , David Abarca , Yucong Zhu , Jonathan C. McKinney

With the forthcoming VLBI images of Sgr A* and M87, simulations of accretion flows onto black holes acquire a special importance to aid with the interpretation of the observations and to test the predictions of different accretion…

General Relativity and Quantum Cosmology · Physics 2019-10-09 Hector Olivares , Oliver Porth , Yosuke Mizuno

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 a set of simulations of relativistic jets from accretion disk initial setup with a new code in Fortran 90 to get numerical solutions of a system of General Relativistic Magnetohydrodynamics (GRMHD) partial differential equations…

High Energy Astrophysical Phenomena · Physics 2016-02-08 R. O. Garcia , S. R. Oliveira

We introduce a new GPU-accelerated general-relativistic magneto-hydrodynamic (GR-MHD) code based on HARM which we call cuHARM. The code is written in CUDA-C and uses OpenMP to parallelize multi-GPU setups. Our code allows us to run high…

High Energy Astrophysical Phenomena · Physics 2023-02-01 Damien Bégué , Asaf Pe'er , Guoqiang Zhang , BinBin Zhang , Benjamin Pevzner

We present a new code for performing general-relativistic radiation-hydrodynamics simulations of accretion flows onto black holes. The radiation field is treated in the optically-thick approximation, with the opacity contributed by Thomson…

High Energy Astrophysical Phenomena · Physics 2015-03-11 Olindo Zanotti , Constanze Roedig , Luciano Rezzolla , Luca Del Zanna

We present MHDuet, an open source evolution code for general relativistic magnetohydrodynamics with neutrino transport. The code solves the full set of Einstein equations coupled to a relativistic, magnetized fluid with an M1 neutrino…

We present the AGATE simulation code, a Python-based framework developed primarily for solving the magnetohydrodynamics (MHD) equations while maintaining adaptability to other equation sets. The code employs a modular, object-oriented…

Plasma Physics · Physics 2025-05-15 Chris Bard , John Dorelli

We develop a numerical scheme for solving a fully special relativistic resistive radiation magnetohydrodynamics. Our code guarantees conservations of total mass, momentum and energy. Radiation energy density and radiation flux are…

High Energy Astrophysical Phenomena · Physics 2019-08-19 Hiroyuki R. Takahashi , Ken Ohsuga

This paper describes the development and testing of a general relativistic magnetohydrodynamic (GRMHD) code to study ideal MHD in the fixed background of a Kerr black hole. The code is a direct extension of the hydrodynamic code of Hawley,…

Astrophysics · Physics 2009-11-07 Jean-Pierre De Villiers , John F. Hawley

The Event Horizon Telescope (EHT), a global sub-millimeter wavelength very long baseline interferometry array, is now resolving the innermost regions around the supermassive black holes Sgr A* and M87. Using black hole images from both…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Angelo Ricarte , Jason Dexter

We propose a new method to conserve the total energy to round-off error in grid-based codes for hydrodynamic simulations with self-gravity. A formula for the energy flux due to the work done by the the self-gravitational force is given, so…

Instrumentation and Methods for Astrophysics · Physics 2012-10-02 Yan-Fei Jiang , Mikhail Belyaev , Jeremy Goodman , James M. Stone

We develop a new, efficient, and accurate method to simulate frequency-domain borehole electromagnetic (EM) measurements acquired in the presence of three-dimensional (3D) variations of the anisotropic subsurface conductivity. The method is…

We present bhlight, a numerical scheme for solving the equations of general relativistic radiation magnetohydrodynamics (GRRMHD) using a direct Monte Carlo solution of the frequency-dependent radiative transport equation. bhlight is…

High Energy Astrophysical Phenomena · Physics 2015-05-20 Benjamin R. Ryan , Joshua C. Dolence , Charles F. Gammie

(Abridged) We here continue our effort to model the behaviour of matter when orbiting or accreting onto a generic black hole by developing a new numerical code employing advanced techniques geared solve the equations of in…

High Energy Astrophysical Phenomena · Physics 2017-02-01 Zakaria Meliani , Yosuke Mizuno , Hector Olivares , Oliver Porth , Luciano Rezzolla , Ziri Younsi

We present a new special relativistic hydrodynamics (SRHD) code capable of handling coexisting ultra-relativistically hot and non-relativistically cold gases. We achieve this by designing a new algorithm for conversion between primitive and…

High Energy Astrophysical Phenomena · Physics 2021-04-21 Po-Hsun Tseng , Hsi-Yu Schive , Tzihong Chiueh

We present two-dimensional general relativistic radiative magnetohydrodynamical simulations of accretion disks around non-rotating stellar-mass black hole. We study the evolution of an equilibrium accreting torus in different grid…

High Energy Astrophysical Phenomena · Physics 2024-03-26 Angelos Karakonstantakis , Debora Lančová , Włodek Kluźniak , Miljenko Čemeljić

The accurate modelling of astrophysical scenarios involving compact objects and magnetic fields, such as the collapse of rotating magnetized stars to black holes or the phenomenology of gamma-ray bursts, requires the solution of the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 B. Giacomazzo , L. Rezzolla