Magritte, a modern software library for 3D radiative transfer: I. Non-LTE atomic and molecular line modelling

Abstract

Radiative transfer is a key component in almost all astrophysical and cosmological simulations. We present Magritte: a modern open-source software library for 3D radiative transfer. It uses a deterministic ray-tracer and formal solver, i.e. it computes the radiation field by tracing rays through the model and solving the radiative transfer equation in its second-order form along a fixed set of rays originating from each point. Magritte can handle structured and unstructured input meshes, as well as smoothed-particle hydrodynamics (SPH) particle data. In this first paper, we describe the numerical implementation, semi-analytic tests and cross-code benchmarks for the non-LTE line radiative transfer module of Magritte. This module uses the radiative transfer solver to self-consistently determine the populations of the quantised energy levels of atoms and molecules using an accelerated Lambda iteration (ALI) scheme. We compare Magritte with the established radiative transfer solvers Ratran (1D) and Lime (3D) on the van Zadelhoff benchmark and present a first application to a simple Keplerian disc model. Comparing with Lime, we conclude that Magritte produces more accurate and more precise results, especially at high optical depth, and that it is faster.

arXiv comment16 pages, accepted in MNRAS

References in corpus (22)

• HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
• An atomic and molecular database for analysis of submillimetre line observations
• An Old Disk That Can Still Form a Planetary System
• The TW Hya Disk at 870 microns: Comparison of CO and Dust Radial Structures
• LIME - a flexible, non-LTE line excitation and radiation transfer method for millimeter and far-infrared wavelengths
• First detection of gas-phase methanol in a protoplanetary disk
• Unexpectedly large mass loss during the thermal pulse cycle of the red giant R Sculptoris!
• Three-Dimensional Dust Radiative Transfer
• Numerical methods for non-LTE line radiative transfer: Performance and convergence characteristics
• 3D-PDR: A new three-dimensional astrochemistry code for treating Photodissociation Regions
• Monte Carlo Radiative Transfer
• ALMA data suggest the presence of a spiral structure in the inner wind of CW Leo
• Gas flow and accretion via spiral streamers and circumstellar disks in a young binary protostar
• SPHRAY: A Smoothed Particle Hydrodynamics Ray Tracer for Radiative Transfer
• The Failure of Monte Carlo Radiative Transfer at Medium to High Optical Depths
• Three-dimensional molecular line transfer: A simulated star-forming region
• ALMA detection of a tentative nearly edge-on rotating disk around the nearby AGB star R~Doradus
• SKIRT: hybrid parallelization of radiative transfer simulations
• NOEMA maps the CO $J=2-1$ environment of the red supergiant $\mu$ Cep
• A disrupted molecular torus around Eta Carinae as seen in 12CO with ALMA
• First detections of H13CO+ and HC15N in the disk around HD 97048: Evidence for a cold gas reservoir in the outer disk
• Gravitational instabilities in a protosolar-like disc III: molecular line detection and sensitivities

Cited by in corpus (17)

• Evolution and Mass Loss of Cool Ageing Stars: a Daedalean Story
• Wind morphology around cool evolved stars in binaries: the case of slowly accelerating oxygen-rich outflows
• ATOMIUM: ALMA tracing the origins of molecules in dust forming oxygen rich M-type stars: Motivation, sample, calibration, and initial results
• LOC program for line radiative transfer
• Is Betelgeuse Really Rotating? Synthetic ALMA Observations of Large-scale Convection in 3D Simulations of Red Supergiants
• Self-consistent dust and non-LTE line radiative transfer with SKIRT
• Magritte, a modern software library for 3D radiative transfer: II. Adaptive ray-tracing, mesh construction and reduction
• 3D simulations of AGB stellar winds -- II. Ray-tracer implementation and impact of radiation on the outflow morphology
• Atomic line radiative transfer with MCFOST I. Code description and benchmarking
• The unusual 3D distribution of NaCl around the AGB star IK Tau
• Radiance Cascades: A Novel High-Resolution Formal Solution for Multidimensional Non-LTE Radiative Transfer
• SPH modelling of AGB wind morphology in hierarchical triple systems \& comparison to observation of R Aql
• Asymmetries in asymptotic giant branch stars and their winds. I. From 3D RHD models to synthetic observables
• Radiative Transfer as a Bayesian Linear Regression problem
• Impact of a binary companion in AGB outflows on CO spectral lines
• A numerically stable comoving frame solver for line radiative transfer
• A rotational line CO cooling rate prescription for AGB outflows