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arXiv · 1003.3878

21cmFAST: A Fast, Semi-Numerical Simulation of the High-Redshift 21-cm Signal

Andrei Mesinger·Steven Furlanetto·Renyue Cen
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Abstract

We introduce a powerful semi-numeric modeling tool, 21cmFAST, designed to efficiently simulate the cosmological 21-cm signal. Our code generates 3D realizations of evolved density, ionization, peculiar velocity, and spin temperature fields, which it then combines to compute the 21-cm brightness temperature. Although the physical processes are treated with approximate methods, we compare our results to a state-of-the-art large-scale hydrodynamic simulation, and find good agreement on scales pertinent to the upcoming observations (>~ 1 Mpc). The power spectra from 21cmFAST agree with those generated from the numerical simulation to within 10s of percent, down to the Nyquist frequency. We show results from a 1 Gpc simulation which tracks the cosmic 21-cm signal down from z=250, highlighting the various interesting epochs. Depending on the desired resolution, 21cmFAST can compute a redshift realization on a single processor in just a few minutes. Our code is fast, efficient, customizable and publicly available, making it a useful tool for 21-cm parameter studies.

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Andrei Mesinger, Steven Furlanetto, Renyue Cen. 2010-03-19. 21cmFAST: A Fast, Semi-Numerical Simulation of the High-Redshift 21-cm Signal. https://doi.org/10.1111/j.1365-2966.2010.17731.x

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