Native Synthetic Imaging of Smoothed Particle Hydrodynamics density fields using gridless Monte Carlo Radiative Transfer

TL;DR

This paper introduces a gridless Monte Carlo Radiative Transfer algorithm for creating synthetic telescope images directly from Smoothed Particle Hydrodynamics density fields, preserving simulation accuracy and enabling advanced astrophysical modeling.

Contribution

The novel algorithm allows direct imaging of SPH density fields without gridding, improving accuracy and applicability in astrophysical simulations.

Findings

Effective in star and planet formation simulations

Preserves SPH simulation accuracy in synthetic imaging

Supports potential future radiative equilibrium modeling

Abstract

An algorithm for creating synthetic telescope images of Smoothed Particle Hydrodynamics (SPH) density fields is presented, which utilises the adaptive nature of the SPH formalism in full. The imaging process uses Monte Carlo Radiative Transfer (MCRT) methods to model the scattering and absorption of photon packets in the density field, which then exit the system and are captured on a pixelated image plane, creating a 2D image (or a 3D datacube, if the photons are also binned by their wavelength). The algorithm is implemented on the density field directly: no gridding of the field is required, allowing the density field to be described to an identical level of accuracy as the simulations that generated it. Some applications of the method to star and planet formation simulations are presented to illustrate the advantages of this new technique, and suggestions as to how this framework could support a Radiative Equilibrium algorithm are also given as an indication for future development.