The Theoretical Astrophysical Observatory: Cloud-Based Mock Galaxy Catalogs*

Abstract

We introduce the Theoretical Astrophysical Observatory (TAO), an online virtual laboratory that houses mock observations of galaxy survey data. Such mocks have become an integral part of the modern analysis pipeline. However, building them requires expert knowledge of galaxy modeling and simulation techniques, significant investment in software development, and access to high performance computing. These requirements make it difficult for a small research team or individual to quickly build a mock catalog suited to their needs. To address this TAO offers access to multiple cosmological simulations and semi-analytic galaxy formation models from an intuitive and clean web interface. Results can be funnelled through science modules and sent to a dedicated supercomputer for further processing and manipulation. These modules include the ability to (1) construct custom observer light cones from the simulation data cubes; (2) generate the stellar emission from star formation histories, apply dust extinction, and compute absolute and/or apparent magnitudes; and (3) produce mock images of the sky. All of TAO's features can be accessed without any programming requirements. The modular nature of TAO opens it up for further expansion in the future.

Massive close pairs measure rapid galaxy assembly in mergers at high redshift

“…Similarly, Kaviraj et al (2016) presented a lightcone image from the Horizon-AGN simulation (e.g., Dubois et al 2014). Therefore, in the future, large cosmological hydrodynamical simulations will support very useful public mock datasets following the examples of the Millennium Run Observatory (O13) and Theoretical Astrophysical Observatory (Bernyk et al 2016). …”

“…To best inform the identification of mergers in survey data, our goal is to create synthetic survey fields from models of galaxy formation, which has been achieved with semianalytic (e.g., Bernyk et al 2016;Overzier et al 2013, hereafter O13) and semi-empirical models (e.g., TaghizadehPopp et al 2015), as well as hybrids of these with the results of hydrodynamical simulations (Hayward et al 2013). In principle, any galaxy formation model sufficiently large, and detailed enough to track subhalos in the mass range of interest, would support these calculations.…”

“…This unique volume is V0 ≈ L 3 /3. This and similar procedures have been applied in many previous modeling analyses (e.g., Blaizot et al 2005;Kitzbichler & White 2007;Henriques et al 2012;Bluck et al 2011;Overzier et al 2013;Taghizadeh-Popp et al 2015;Bernyk et al 2016).…”

“…Their cosmological sizes allow us to convert these simulations into mock catalogs in the same way as has been done for several years using semianalytic and semi-empirical models, for example by using the lightcone technique to create mock galaxy catalogs as a function of angular coordinates and redshift (e. Bernyk et al 2016;Overzier et al 2013;TaghizadehPopp et al 2015). This has the benefit of bringing our comparisons between theory and data into the same language.…”

Physical drivers of galaxies’ cold-gas content: exploring environmental and evolutionary effects with Dark Sage

“…Galaxy catalogues built from Dark Sage are available through the Theoretical Astrophysical Observatory (Bernyk et al 2016). 4 Here, photometric properties and light-cones for Dark Sage galaxies can be constructed.…”