MultiDark-Galaxies: data release and first results

Abstract

We present the public release of the MULTIDARK-GALAXIES: three distinct galaxy catalogues derived from one of the Planck cosmology MULTIDARK simulations (i.e. MDPL2, with a volume of (1 h −1 Gpc) 3 and mass resolution of 1.5 × 10 9 h −1 M ) by applying the semi-analytic models GALACTICUS, SAG, and SAGE to it. We compare the three models and their conformity with observational data for a selection of fundamental properties of galaxies like stellar mass function, star formation rate, cold gas fractions, and metallicities -noting that they sometimes perform differently reflecting model designs and calibrations. We have further selected galaxy subsamples of the catalogues by number densities in stellar mass, cold gas mass, and star formation rate in order to study the clustering statistics of galaxies. We show that despite different treatment of orphan galaxies, i.e. galaxies that lost their dark-matter host halo due to the finite mass resolution of the N -body simulation or tidal stripping, the clustering signal is comparable, and reproduces the observations in all three models -in particular when selecting samples based upon stellar mass. Our catalogues provide a powerful tool to study galaxy formation within a volume comparable to those probed by on-going and future photometric and redshift surveys. All model data consisting of a range of galaxy propertiesincluding broad-band SDSS magnitudes -are publicly available.

How galaxies populate haloes in very low-density environments

“…The MDPL2-SAG 1 catalogue is part of the MultiDark-Galaxies catalogues (Knebe et al 2018), publicly available at the Cos-moSim 2 and Skies & Universes 3 databases. This catalogue was constructed by applying the semi-analytic model of galaxy formation and evolution SAG (acronym for Semi-Analytic Galaxies) to the dark matter haloes of the MDPL2 cosmological simulation.…”

Exploring the high-mass end of the stellar mass function of star-forming galaxies at cosmic noon

“…With our study of massive galaxies across diverse environments at high redshifts, the results from the SHELA footprint may prove useful in calibrating abundance matching methods for massive galaxies. Knebe et al (2018) also utilize the MDPL2 dark matter simulation, and model the physics of baryons within dark matter halos by implementing semi-analytic models (SAMs). SAMs are models of galaxy evolution that track overall properties such as gas temperature and feedback processes in order to follow the growth of galaxies across cosmic time (Somerville & Davé 2015).…”

“…The flexible and inexpensive nature of SAMs allows for different physical models of galaxy evolution and prescriptions for their growth over time to be explored. With this in mind, Knebe et al (2018) applied three SAMs to the dark matter halos and merger trees from MDPL2. The three SAMs, GALACTICUS (Benson 2012), SAG (Cora et al 2018), and SAGE (Croton et al 2016(Croton et al ) differ in their et al (2007, who showed a factor of 100 difference between massive galaxy number densities from the Millennium Run SAM (De Lucia et al 2006) and observations in the Palomar/DEEP2 survey (e.g., Davis et al 2003, Giavalisco et al 2004, Bundy et al 2005, Davis et al 2007) at z ∼ 2.…”

Compact groups from semi-analytical models of galaxy formation – I. A comparative study of frequency and nature

“…We analyzed four SAMs run on the Millennium simulation (MS, Springel et al 2005), two SAMs run on the Millennium simulation II (MSII, Boylan-Kolchin et al 2009), and one SAM run on the Multidark Simulation (MDPL2, Knebe et al 2018). These SAMs are those of: In Appendix A, we quote the queries used to retrieve data from the public outputs of the SAMs.…”

“…The majority of the models used here are part of the Millennium run simulation project (Lemson & Virgo Consortium 2006). To improve our comparison, we have also included a SAM that was implemented in a different large cosmological simulation performed by the MultiDark project 1 (Knebe et al 2018).…”