Bibcode
Vulcani, Benedetta; De Lucia, Gabriella; Poggianti, Bianca M.; Bundy, Kevin; More, Surhud; Calvi, Rosa
Bibliographical reference
The Astrophysical Journal, Volume 788, Issue 1, article id. 57, 20 pp. (2014).
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6
2014
Journal
Citations
21
Refereed citations
21
Description
We present a comparison between the observed galaxy stellar mass
function and the one predicted from the De Lucia & Blaizot
semi-analytic model applied to the Millennium Simulation, for cluster
satellites and galaxies in the field (meant as a wide portion of the
sky, including all environments), in the local universe (z ~ 0.06), and
at intermediate redshift (z ~ 0.6), with the aim to shed light on the
processes which regulate the mass distribution in different
environments. While the mass functions in the field and in its finer
environments (groups, binary, and single systems) are well matched in
the local universe down to the completeness limit of the observational
sample, the model overpredicts the number of low-mass galaxies in the
field at z ~ 0.6 and in clusters at both redshifts. Above M *
= 1010.25 M ⊙, it reproduces the observed
similarity of the cluster and field mass functions but not the observed
evolution. Our results point out two shortcomings of the model: an
incorrect treatment of cluster-specific environmental effects and an
overefficient galaxy formation at early times (as already found by,
e.g., Weinmann et al.). Next, we consider only simulations. Also using
the Guo et al. model, we find that the high-mass end of the mass
functions depends on halo mass: only very massive halos host massive
galaxies, with the result that their mass function is flatter. Above M
* = 109.4 M ⊙, simulations show
an evolution in the number of the most massive galaxies in all
environments. Mass functions obtained from the two prescriptions are
different, however, results are qualitatively similar, indicating that
the adopted methods to model the evolution of central and satellite
galaxies still have to be better implemented in semi-analytic models.