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arXiv · 2607.16059

OpenCosmo: Community Portal and Analysis Framework for Flagship Cosmological Simulations

Patrick R. Wells·Michael Buelhmann·Patricia Larsen·William M. Hicks·Manpreet Dhillon·Idunnuoluwa A. Adeniji·Katrin Heitmann·Salman Habib·Benoit Côté·Thomas Uram·Gideon McFarland·Andrew Hearin·Ezar Shinabro·Michael E. Papka
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Abstract

Cosmology is a precision observational science, and large simulations are necessary components of many analyses. These simulations are computationally expensive and produce massive, complex datasets; sharing them widely -- to enable further explorations, comparison with observations, and communication with general audiences -- is crucial to realizing their scientific value. In this paper, we introduce the OpenCosmo project, which provides flexible access to, and analysis of, flagship cosmological simulations performed with HACC. A web-based portal (https://opencosmo.science) serves custom subsets -- halo catalogs, profiles, particles, galaxy catalogs, and lightcone catalogs and maps -- from simulations including the two-trillion-particle Frontier-E gravity-only run, Last Journey, Discovery, and a 64-member hydrodynamic suite. A companion Python toolkit analyzes the returned data and scales without modification from laptop-sized subsets to full simulations on supercomputers. OpenCosmo supports multiple levels of interaction, from browser-based search and download to programmatic and AI-agent-driven workflows, by integrating with existing high-performance computing and data infrastructure. Its architecture, built on Globus services, provides a scalable and adaptable framework that can be extended to other scientific domains seeking to couple data sharing with computational capability.

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Patrick R. Wells, Michael Buelhmann, Patricia Larsen, William M. Hicks, Manpreet Dhillon, Idunnuoluwa A. Adeniji, Katrin Heitmann, Salman Habib, Benoit Côté, Thomas Uram, Gideon McFarland, Andrew Hearin, Ezar Shinabro, Michael E. Papka. 2026-07-17. OpenCosmo: Community Portal and Analysis Framework for Flagship Cosmological Simulations. https://arxiv.org/abs/2607.16059

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