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arXiv · 1909.09876

Trigonometric Extension of the Geometric Correction Factor: Prototype for adding precision to adaptive ray tracing in ENZO

Abstract

In this paper, we describe a method designed to add precision to radiation simulations in the adaptive mesh refinement cosmological hydrodynamics code ENZO. We build upon the geometric correction factor described in \textit{ENZO+MORAY: radiation hydrodynamics adaptive mesh refinement simulations with adaptive ray tracing} (Wise and Abel 2011) which accounts for partial coverage of a ray's solid angle with a cube. Because of this geometric mismatch in the methods to approximate this, there are artifacts in the radiation field. Here, we address the two-dimensional extension, which acts as a sufficient estimate of the three-dimensional case and, in practice, the Hierarchical Equal Area isoLatitude Pixelization of the sphere (HEALPix) (Gorski 2005). We will demonstrate the value of an extension to the geometric correction factor and lay the groundwork for a future implementation to ENZO to improve simulations of radiation from point sources.

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Collin Cunningham. 2019-09-21. Trigonometric Extension of the Geometric Correction Factor: Prototype for adding precision to adaptive ray tracing in ENZO. https://arxiv.org/abs/1909.09876

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