Is main-sequence galaxy star formation controlled by halo mass accretion?

Aldo Rodríguez-Puebla, Joel R. Primack, Peter Behroozi, S. M. Faber

Research output: Contribution to journalArticlepeer-review

65 Scopus citations

Abstract

The galaxy stellar-to-halo mass relation (SHMR) is nearly time-independent for z < 4. We therefore construct a time-independent SHMR model for central galaxies, wherein the in situ star formation rate (SFR) is determined by the halo mass accretion rate (MAR), which we call stellar halo accretion rate coevolution (SHARC). We show that the ~0.3 dex dispersion of the halo MAR matches the observed dispersion of the SFR on the star formation main sequence (MS). In the context of 'bathtub'-type models of galaxy formation, SHARC leads to mass-dependent constraints on the relation between SFR and MAR. Despite its simplicity and the simplified treatment of mass growth from mergers, the SHARC model is likely to be a good approximation for central galaxies with M* = 109-1010.5M⊙ that are on the MS, representing most of the star formation in the Universe. SHARC predictions agree with observed SFRs for galaxies on the MS at low redshifts, agree fairly well at z ~ 4, but exceed observations at z ≳ 4. Assuming that the interstellar gas mass is constant for each galaxy (the 'equilibrium condition' in bathtub models), the SHARC model allows calculation of net mass loading factors for inflowing and outflowing gas.With assumptions about preventive feedback based on simulations, SHARC allows calculation of galaxy metallicity evolution. If galaxy SFRs indeed track halo MARs, especially at low redshifts, that may help explain the success of models linking galaxy properties to haloes (including age-matching) and the similarities between two-halo galaxy conformity and halo mass accretion conformity.

Original languageEnglish (US)
Pages (from-to)2592-2606
Number of pages15
JournalMonthly Notices of the Royal Astronomical Society
Volume455
Issue number3
DOIs
StatePublished - Jan 21 2016
Externally publishedYes

Keywords

  • Cosmology: theory
  • Galaxies: evolution
  • Galaxies: haloes
  • Galaxies: luminosity function, mass function
  • Galaxies: star formation

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint

Dive into the research topics of 'Is main-sequence galaxy star formation controlled by halo mass accretion?'. Together they form a unique fingerprint.

Cite this