Arepo-MCRT: Monte Carlo radiation hydrodynamics on a moving mesh

Jun 02, 2020 - 11:00 am to 12:00 pm
Aaron Smith (MIT) via zoom

I will discuss Arepo-MCRT, a Monte Carlo radiative transfer (MCRT) radiation hydrodynamics (RHD) solver for the unstructured moving-mesh code Arepo. The method is designed for general multiple scattering problems in both optically-thin and -thick conditions. It incorporates numerous efficiency improvements and noise reduction schemes to help overcome efficiency barriers that typically inhibit convergence. These include continuous absorption and energy deposition, photon weighting and luminosity boosting, local packet merging and splitting, path-based statistical estimators, conservative (face-centered) momentum coupling, adaptive convergence between time-steps, Implicit Monte Carlo (IMC) for thermal emission, and discrete diffusion Monte Carlo (DDMC) for unresolved scattering. I will focus on unique aspects of the implementation, advantages for various astrophysical contexts, and briefly highlight related radiative transfer projects from protostars to high-redshift galaxies.