A semi-analytical perspective on massive galaxies at z ∼ 0.55. Issue 1 (19th March 2019)

• Record Type: Journal Article
• Authors: Stoppacher, D; Prada, F; Montero-Dorta, A D; Rodríguez-Torres, S; Knebe, A; Favole, G; Cui, W; Benson, A J; Behrens, C; Klypin, A A
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 486:Issue 1(2019)
• Page Start: 1316
• Page End: 1331
• Publication Date: 2019-03-19
• Subjects: galaxies: evolution -- galaxies: haloes -- cosmology: theory -- dark matter; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/stz797
• Languages: English
• ISSNs: 0035-8711

Abstract

ABSTRACT: The most massive and luminous galaxies in the Universe serve as powerful probes to study the formation of structure, the assembly of mass, and cosmology. However, their detailed formation and evolution is still barely understood. Here we extract a sample of massive mock galaxies from the semi-analytical model of galaxy formation (SAM)galacticus from theMultiDark-Galaxies by replicating theCMASS photometric selection from theSDSS -iii Baryon Oscillation Spectroscopic Survey (BOSS ). The comparison of thegalacticus CMASS-mock withBOSS –CMASS data allows us to explore different aspects of the massive galaxy population at 0.5 < z < 0.6, including the galaxy–halo connection and the galaxy clustering. We find good agreement between our modelled galaxies and observations regarding the galaxy–halo connection, but our CMASS-mock overestimates the clustering amplitude of the two-point correlation function due to a smaller number density compared toBOSS, a lack of blue objects, and a small intrinsic scatter in stellar mass at fixed halo mass of <0.1 dex. To alleviate this problem, we construct an alternative mock catalogue mimicking theCMASS colour–magnitude distribution by randomly down-sampling the SAM catalogue. This CMASS-mock reproduces the clustering ofCMASS galaxies within 1σ and shows some environmental dependency of star formation properties that could be connected to the quenching of star formation and the assembly bias.