A new ionisation network and radiation transport module in PLUTO

TL;DR

This paper introduces a comprehensive ionisation network and radiation transport module in the PLUTO code, enabling detailed astrophysical simulations involving ionisation, radiation, and dust processes across a wide temperature range.

Contribution

The authors develop and integrate a new ionisation network and radiation transport module into PLUTO, capable of handling complex ionisation states and radiation interactions in 3D astrophysical contexts.

Findings

Validated the modules with numerical tests showing reliability.

Demonstrated compatibility with 3D simulations and spherical symmetry assumptions.

Provided tools for post-processing to obtain spectra and column densities.

Abstract

We introduce a new general-purpose time-dependent ionisation network (IN) and a radiation transport (RT) module in the magneto-hydrodynamic (MHD) code PLUTO. Our ionisation network is reliable for temperatures ranging from 5e3 to 3e8 K, and includes all ionisation states of H, He, C, N, O, Ne, Mg, Si, S and Fe making it suitable for studying a variety of astrophysical scenarios. Radiation loss for each ion-electron pair is calculated using CLOUDY-17 data on-the-fly. Photo-ionisation and charge exchange are the chemical heating mechanisms. The IN is fully coupled to the radiation transport module over a very large range of opacities at different frequencies. The RT module employs a method of short characteristics assuming spherical symmetry. The radiation module requires the assumption of spherical symmetry, while the IN is compatible with full 3D. We also include a simple prescription for dust opacity, grain destruction, and the dust contribution to radiation pressure. We present numerical tests to show the reliability and limitations of the new modules. We also present a post-processing tool to calculate projected column densities and emission spectra.