The redshift evolution of the distribution of star formation among dark matter halos as seen in the infrared
Résumé
Recent studies have revealed a strong correlation between the star formation rate (SFR)
and stellar mass of the majority of star-forming galaxies, the so-called star-forming main
sequence. An empirical modeling approach (the 2-SFM framework) that distinguishes between
the main sequence and rarer starburst galaxies is capable of reproducing most statistical
properties of infrared galaxies, such as number counts, luminosity functions, and redshift
distributions. In this paper, we extend this approach by establishing a connection between
stellar mass and halo mass with the technique of abundance matching. Based on a few simple
assumptions and a physically motivated formalism, our model successfully predicts the
(cross-)power spectra of the cosmic infrared background (CIB), the cross-correlation
between CIB and cosmic microwave background (CMB) lensing, and the correlation functions
of bright, resolved infrared galaxies measured by Herschel,
Planck, ACT, and SPT. We use this model to infer the redshift
distribution of CIB-anisotropies and of the CIB × CMB lensing signal, as well as the level
of correlation between CIB-anisotropies at different wavelengths. We study the link
between dark matter halos and star-forming galaxies in the framework of our model. We
predict that more than 90% of cosmic star formation activity occurs in halos with masses
between 1011.5 and 1013.5 M⊙. If taking
subsequent mass growth of halos into account, this implies that the majority of stars were
initially (at z > 3) formed in the progenitors of
clusters
(Mh(z = 0) > 1013.5 M⊙),
then in groups
(1012.5 < Mh(z = 0) < 1013.5 M⊙)
at 0.5 < z < 3, and
finally in Milky-Way-like halos
(1011.5 < Mh(z = 0) < 1012.5 M⊙)
at z < 0.5. At all redshifts, the dominant
contribution to the SFR density stems from halos of mass
~1012 M⊙, in which the instantaneous star
formation efficiency – defined here as the ratio between SFR and baryonic accretion rate –
is maximal (~70%). The strong redshift-evolution of SFR in the galaxies that dominate the
CIB is thus plausibly driven by increased accretion from the cosmic web onto halos of this
characteristic mass scale. Material (effective spectral energy distributions, differential
emissivities of halos, relations between Mh and SFR)
associated to this model is available at http://irfu.cea.fr/Sap/Phocea/Page/index.php?id=537.
Origine : Publication financée par une institution
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