Projecting SPH Particles in Adaptive Environments

Abstract

The reconstruction of a smooth field onto a fixed grid is a necessary step for direct comparisons to various real-world observations. Projecting SPH data onto a fixed grid becomes challenging in adaptive environments, where some particles may have smoothing lengths far below the grid size, whilst others are resolved by thousands of pixels. In this paper we show how the common approach of treating particles below the grid size as Monte Carlo tracers of the field leads to significant reconstruction errors, and despite good convergence properties is unacceptable for use in synthetic observations in astrophysics. We propose a new method, where particles smaller than the grid size are `blitted' onto the grid using a high-resolution pre-calculated kernel, and those close to the grid size are subsampled, that allows for converged predictions for projected quantities at all grid sizes.

2021 International SPHERIC Workshop. Please cite arXiv version if possible as ADS cannot track Proceeding references. Updated to fix broken figures

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Cited by in corpus (5)

• EAGLE-like simulation models do not solve the entropy core problem in groups and clusters of galaxies
• The complex interplay of AGN jet-inflated bubbles and the intracluster medium
• Active galactic nuclei jets simulated with smoothed particle hydrodynamics
• The THESAN-ZOOM project: Star-formation efficiencies in high-redshift galaxies
• Winds versus jets: a comparison between black hole feedback modes in simulations of idealized galaxy groups and clusters