A multiphysics and multiscale software environment for modeling astrophysical systems

Abstract

We present MUSE, a software framework for combining existing computational tools for different astrophysical domains into a single multiphysics, multiscale application. MUSE facilitates the coupling of existing codes written in different languages by providing inter-language tools and by specifying an interface between each module and the framework that represents a balance between generality and computa-tional efficiency. This approach allows scientists to use combinations of codes to solve highly-coupled problems without the need to write new codes for other domains or significantly alter their existing codes. MUSE currently incorporates the domains of stellar dynamics, stellar evolution and stellar hydrodynamics for studying generalized stellar systems. We have now reached a "Noah's Ark" milestone, with (at least) two available numerical solvers for each domain. MUSE can treat multi-scale and multi-physics systems in which the time-and size-scales are well separated, like simulating the evolution of planetary systems, small stellar associations, dense stellar clusters, galaxies and galactic nuclei. In this paper we describe three examples calculated using MUSE: the merger of two galaxies, the merger of two evolving stars, and a hybrid N -body simulation. In addition, we demonstrate an implementation of MUSE on a distributed computer which may also include special-purpose hardware, such as GRAPEs or GPUs, to accelerate computations. The current MUSE code base is publicly available as open source at http://muse.li.

External photoevaporation of circumstellar discs constrains the time-scale for planet formation

“…Since planet formation related processes seem to start very quickly in circumstellar disks (< 0.1 − 1 Myr, Najita & Kenyon (2014); Manara et al (2018)), understanding the mechanisms that affect disk evolution is directly connected to understanding planetary system formation and survival. The Sun was probably born within a star cluster (Portegies Zwart et al 2009), so discerning how the E-mail: fconcha@strw.leidenuniv.nl cluster environment affects the evolution of the disks can help us comprehend the origins of the Solar System.…”

Gravitational waves from in-spirals of compact objects in binary common-envelope evolution

“…To test our semi-analytical calculations, we perform a hydrodynamical simulation for the case M + Menv = 8M⊙, m = 0.6M⊙. Our simulation is run via the AMUSE framework (Portegies Zwart et al 2009), which allows us to combine different type of codes. We use the same density profile for the 8M⊙ red giant as above, and convert it to a 3-dimensional smoothed-particle-hydrodynamics (SPH) model with 250000 gas particles.…”

The Oceanographic Multipurpose Software Environment (OMUSE v1.0)

“…The main developments compared with AMUSE, apart from the addition of oceanographic codes, are improvements in grid support, amongst these support for curvilinear grids and extensive framework support for grid remappings and grid generation routines. In addition, a number of domain-specific units and utility libraries and support for various file formats, such as NetCDF (Rew and Davis, 1990) output, have been added.…”

“…In the present version, OMUSE contains an initial set of ocean models, namely QG (a quasi-geostrophic solver), AD-CIRC, POP and SWAN (ideally one would like to reach a "Noah's arc" milestone of having at least two independent application codes per domain; Portegies Zwart et al, 2009). The implementation in OMUSE of the code interfaces is described in this section.…”