Messenger Monte-Carlo MAPPINGS V (M^3) -- A self-consistent three-dimensional photoionization code

TL;DR

M^3 is a self-consistent 3D photoionization code using Monte Carlo radiative transfer, enabling detailed modeling of complex nebula geometries for astrophysical research.

Contribution

The paper introduces M^3, a novel 3D photoionization code with advanced Monte Carlo techniques and comprehensive microphysics, surpassing previous models limited to simple geometries.

Findings

Successfully passed Lexington/Meudon benchmark tests.

Capable of modeling complex nebula geometries.

Suitable for analyzing high-resolution astrophysical data.

Abstract

The Messenger Interface Monte-Carlo Mappings V (M^3) is a photoionization code adopting the fully self-consistent Monte-Carlo radiative transfer technique, which presents a major advance over previous photoionization models with simple geometries. M^3 is designed for modeling nebulae in arbitrary three-dimensional geometries. In this paper, we describe the Monte-Carlo radiative transfer technique and the microphysics implemented in M^3, including the photoionization, collisional ionization, the free-free and free-bound recombination, and two-photon radiation. We put M^3 through the Lexington/Meudon benchmarks to test the reliability of the new code. We apply M^3 to three HII region models with fiducial geometries, demonstrating that M^3 is capable of dealing with nebulae with complex geometries. M^3 is a promising tool for understanding emission-line behavior in the era of SDSS-V/LVM and JWST, which will provide high-quality data of spatially-resolved nearby HII regions and highly turbulent local and high-redshift HII regions.