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arXiv · 1308.2669

The AGORA High-Resolution Galaxy Simulations Comparison Project

Ji-hoon Kim·Tom Abel·Oscar Agertz·Greg L. Bryan·Daniel Ceverino·Charlotte Christensen·Charlie Conroy·Avishai Dekel·Nickolay Y. Gnedin·Nathan J. Goldbaum·Javiera Guedes·Oliver Hahn·Alexander Hobbs·Philip F. Hopkins·Cameron B. Hummels·Francesca Iannuzzi·Dusan Keres·Anatoly Klypin·Andrey V. Kravtsov·Mark R. Krumholz·Michael Kuhlen·Samuel N. Leitner·Piero Madau·Lucio Mayer·Christopher E. Moody·Kentaro Nagamine·Michael L. Norman·Jose Oñorbe·Brian W. O'Shea·Annalisa Pillepich·Joel R. Primack·Thomas Quinn·Justin I. Read·Brant E. Robertson·Miguel Rocha·Douglas H. Rudd·Sijing Shen·Britton D. Smith·Alexander S. Szalay·Romain Teyssier·Robert Thompson·Keita Todoroki·Matthew J. Turk·James W. Wadsley·John H. Wise·Adi Zolotov
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Abstract

We introduce the AGORA project, a comprehensive numerical study of well-resolved galaxies within the LCDM cosmology. Cosmological hydrodynamic simulations with force resolutions of ~100 proper pc or better will be run with a variety of code platforms to follow the hierarchical growth, star formation history, morphological transformation, and the cycle of baryons in and out of 8 galaxies with halo masses M_vir ~= 1e10, 1e11, 1e12, and 1e13 Msun at z=0 and two different ("violent" and "quiescent") assembly histories. The numerical techniques and implementations used in this project include the smoothed particle hydrodynamics codes GADGET and GASOLINE, and the adaptive mesh refinement codes ART, ENZO, and RAMSES. The codes will share common initial conditions and common astrophysics packages including UV background, metal-dependent radiative cooling, metal and energy yields of supernovae, and stellar initial mass function. These are described in detail in the present paper. Subgrid star formation and feedback prescriptions will be tuned to provide a realistic interstellar and circumgalactic medium using a non-cosmological disk galaxy simulation. Cosmological runs will be systematically compared with each other using a common analysis toolkit, and validated against observations to verify that the solutions are robust - i.e., that the astrophysical assumptions are responsible for any success, rather than artifacts of particular implementations. The goals of the AGORA project are, broadly speaking, to raise the realism and predictive power of galaxy simulations and the understanding of the feedback processes that regulate galaxy "metabolism." The proof-of-concept dark matter-only test of the formation of a galactic halo with a z=0 mass of M_vir ~= 1.7e11 Msun by 9 different versions of the participating codes is also presented to validate the infrastructure of the project.

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Ji-hoon Kim, Tom Abel, Oscar Agertz, Greg L. Bryan, Daniel Ceverino, Charlotte Christensen, Charlie Conroy, Avishai Dekel, Nickolay Y. Gnedin, Nathan J. Goldbaum, Javiera Guedes, Oliver Hahn, Alexander Hobbs, Philip F. Hopkins, Cameron B. Hummels, Francesca Iannuzzi, Dusan Keres, Anatoly Klypin, Andrey V. Kravtsov, Mark R. Krumholz, Michael Kuhlen, Samuel N. Leitner, Piero Madau, Lucio Mayer, Christopher E. Moody, Kentaro Nagamine, Michael L. Norman, Jose Oñorbe, Brian W. O'Shea, Annalisa Pillepich, Joel R. Primack, Thomas Quinn, Justin I. Read, Brant E. Robertson, Miguel Rocha, Douglas H. Rudd, Sijing Shen, Britton D. Smith, Alexander S. Szalay, Romain Teyssier, Robert Thompson, Keita Todoroki, Matthew J. Turk, James W. Wadsley, John H. Wise, Adi Zolotov. 2013-12-25. The AGORA High-Resolution Galaxy Simulations Comparison Project. https://doi.org/10.1088/0067-0049%2F210%2F1%2F14

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