The Arepo public code release
Abstract
We introduce the public version of the cosmological magnetohydrodynamical movingmesh simulation code Arepo. This version contains a finitevolume magnetohydrodynamics algorithm on an unstructured, dynamic Voronoi tessellation coupled to a treeparticlemesh algorithm for the Poisson equation either on a Newtonian or cosmologically expanding spacetime. Timeintegration is performed adopting local timestep constraints for each cell individually, solving the fluxes only across active interfaces, and calculating gravitational forces only between active particles, using an operatorsplitting approach. This allows simulations with high dynamic range to be performed efficiently. Arepo is a massively distributedmemory parallel code, using the Message Passing Interface (MPI) communication standard and employing a dynamical workload and memory balancing scheme to allow optimal use of multinode parallel computers. The employed parallelization algorithms of Arepo are deterministic and produce binaryidentical results when rerun on the same machine and with the same number of MPI ranks. A simple primordial cooling and star formation model is included as an example of subresolution models commonly used in simulations of galaxy formation. Arepo also contains a suite of computationally inexpensive test problems, ranging from idealized tests for automated code verification to scaleddown versions of cosmological galaxy formation simulations, and is extensively documented in order to assist adoption of the code by new scientific users.
 Publication:

arXiv eprints
 Pub Date:
 September 2019
 arXiv:
 arXiv:1909.04667
 Bibcode:
 2019arXiv190904667W
 Keywords:

 Astrophysics  Instrumentation and Methods for Astrophysics;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 Astrophysics  Astrophysics of Galaxies;
 Physics  Computational Physics
 EPrint:
 39 pages, 15 figures, accepted in ApJS, https://www.arepocode.org, repository: https://gitlab.mpcdf.mpg.de/vrs/arepo