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arXiv · 2006.01697

The Last Journey. I. An Extreme-Scale Simulation on the Mira Supercomputer

Katrin Heitmann·Nicholas Frontiere·Esteban Rangel·Patricia Larsen·Adrian Pope·Imran Sultan·Thomas Uram·Salman Habib·Hal Finkel·Danila Korytov·Eve Kovacs·Silvio Rizzi·Joe Insley
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Abstract

The Last Journey is a large-volume, gravity-only, cosmological N-body simulation evolving more than 1.24 trillion particles in a periodic box with a side-length of 5.025Gpc. It was implemented using the HACC simulation and analysis framework on the BG/Q system, Mira. The cosmological parameters are chosen to be consistent with the results from the Planck satellite. A range of analysis tools have been run in situ to enable a diverse set of science projects, and at the same time, to keep the resulting data amount manageable. Analysis outputs have been generated starting at redshift z~10 to allow for construction of synthetic galaxy catalogs using a semi-analytic modeling approach in post-processing. As part of our in situ analysis pipeline we employ a new method for tracking halo sub-structures, introducing the concept of subhalo cores. The production of multi-wavelength synthetic sky maps is facilitated by generating particle lightcones in situ, also beginning at z~10. We provide an overview of the simulation set-up and the generated data products; a first set of analysis results is presented. A subset of the data is publicly available.

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Katrin Heitmann, Nicholas Frontiere, Esteban Rangel, Patricia Larsen, Adrian Pope, Imran Sultan, Thomas Uram, Salman Habib, Hal Finkel, Danila Korytov, Eve Kovacs, Silvio Rizzi, Joe Insley. 2020-06-02. The Last Journey. I. An Extreme-Scale Simulation on the Mira Supercomputer. https://doi.org/10.3847/1538-4365/abcc67

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