Comparing Galaxy Clustering in Horizon-AGN Simulated Lightcone Mocks and VIDEO Observations

Abstract

Hydrodynamical cosmological simulations have recently made great advances in reproducing galaxy mass assembly over cosmic time - as often quantified from the comparison of their predicted stellar mass functions to observed stellar mass functions from data. In this paper we compare the clustering of galaxies from the hydrodynamical cosmological simulated lightcone Horizon-AGN, to clustering measurements from the VIDEO survey observations. Using mocks built from a VIDEO-like photometry, we first explore the bias introduced into clustering measurements by using stellar masses and redshifts derived from SED-fitting, rather than the intrinsic values. The propagation of redshift and mass statistical and systematic uncertainties in the clustering measurements causes us to underestimate the clustering amplitude. We find then that clustering and halo occupation distribution (HOD) modelling results are qualitatively similar in Horizon-AGN and VIDEO. However at low stellar masses Horizon-AGN underestimates the observed clustering by up to a factor of ~3, reflecting the known excess stellar mass to halo mass ratio for Horizon-AGN low mass haloes, already discussed in previous works. This reinforces the need for stronger regulation of star formation in low mass haloes in the simulation. Finally, the comparison of the stellar mass to halo mass ratio in the simulated catalogue, inferred from angular clustering, to that directly measured from the simulation, validates HOD modelling of clustering as a probe of the galaxy-halo connection.

17 pages, 10 figures, accepted MNRAS 7th October 2019

References in corpus (12)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Properties of galaxies reproduced by a hydrodynamic simulation
• Building Merger Trees from Cosmological N-body Simulations
• On the interplay between star formation and feedback in galaxy formation simulations
• Bent by baryons: the low mass galaxy-halo relation
• The galaxy-halo connection from a joint lensing, clustering and abundance analysis in the CFHTLenS/VIPERS field
• Probing the galaxy-halo connection in UltraVISTA to $z\sim 2$
• Radio-Quiet Quasars in the VIDEO Survey: Evidence for AGN-powered radio emission at S_1.4GHz < 1 mJy
• Horizon-AGN virtual observatory - 1. SED-fitting performance and forecasts for future imaging surveys
• The angular correlations of galaxies in the COSMOS field
• The Lopsidedness of Satellite Galaxy Systems in $\Lambda$CDM simulations
• Mock observations with the Millennium simulation: Cosmological downsizing and intermediate redshift observations

Cited by in corpus (5)

• UNCOVERing the extended strong lensing structures of Abell 2744 with the deepest JWST imaging
• COSMOS2020: The cosmic evolution of the stellar-to-halo mass relation for central and satellite galaxies up to z~5
• SH$\alpha$DE: Survey description and mass-kinematics scaling relations for dwarf galaxies
• Tracing the galaxy-halo connection with galaxy clustering in COSMOS-Web from z = 0.1 to z ~ 12
• Intrinsic correlations of galaxy sizes in a hydrodynamical cosmological simulation