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arXiv · 1301.4498

Nyx: A Massively Parallel AMR Code for Computational Cosmology

Ann Almgren·John Bell·Mike Lijewski·Zarija Lukić·Ethan Van Andel
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Abstract

We present a new N-body and gas dynamics code, called Nyx, for large-scale cosmological simulations. Nyx follows the temporal evolution of a system of discrete dark matter particles gravitationally coupled to an inviscid ideal fluid in an expanding universe. The gas is advanced in an Eulerian framework with block-structured adaptive mesh refinement (AMR); a particle-mesh (PM) scheme using the same grid hierarchy is used to solve for self-gravity and advance the particles. Computational results demonstrating the validation of Nyx on standard cosmological test problems, and the scaling behavior of Nyx to 50,000 cores, are presented.

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Ann Almgren, John Bell, Mike Lijewski, Zarija Lukić, Ethan Van Andel. 2013-01-18. Nyx: A Massively Parallel AMR Code for Computational Cosmology. https://doi.org/10.1088/0004-637x/765/1/39

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