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arXiv · 1806.10564

Synthetic Gaia surveys from the FIRE cosmological simulations of Milky Way-mass galaxies

Robyn E. Sanderson·Andrew Wetzel·Sarah Loebman·Sanjib Sharma·Philip F. Hopkins·Shea Garrison-Kimmel·Claude-André Faucher-Giguère·Dušan Kereš·Eliot Quataert
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Abstract

With Gaia Data Release 2, the astronomical community is entering a new era of multidimensional surveys of the Milky Way. This new phase-space view of our Galaxy demands new tools for comparing observations to simulations of Milky-Way-mass galaxies in a cosmological context, to test the physics of both dark matter and galaxy formation. We present ananke, a framework for generating synthetic phase-space surveys from high-resolution baryonic simulations, and use it to generate a suite of synthetic surveys resembling Gaia DR2 in data structure, magnitude limits, and observational errors. We use three cosmological simulations of Milky-Way-mass galaxies from the Latte suite of the Feedback In Realistic Environments (FIRE) project, which feature self-consistent clustering of star formation in dense molecular clouds and thin stellar/gaseous disks in live cosmological halos with satellite dwarf galaxies and stellar halos. We select three solar viewpoints from each simulation to generate nine synthetic Gaia-like surveys. We sample synthetic stars by assuming each star particle (of mass 7070 $M_{\odot}$) represents a single stellar population. At each viewpoint, we compute dust extinction from the simulated gas metallicity distribution and apply a simple error model to produce a synthetic Gaia-like survey that includes both observational properties and a pointer to the generating star particle. We provide the complete simulation snapshot at $z = 0$ for each simulated galaxy. We describe data access points, the data model, and plans for future upgrades. These synthetic surveys provide a tool for the scientific community to test analysis methods and interpret Gaia data.

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Robyn E. Sanderson, Andrew Wetzel, Sarah Loebman, Sanjib Sharma, Philip F. Hopkins, Shea Garrison-Kimmel, Claude-André Faucher-Giguère, Dušan Kereš, Eliot Quataert. 2018-06-27. Synthetic Gaia surveys from the FIRE cosmological simulations of Milky Way-mass galaxies. https://doi.org/10.3847/1538-4365%2Fab5b9d

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