2006/07/11 by Charlie Conroy, Francisco Prada, Jeffrey A. Newman +11 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/509632
published as Astrophys.J.654:153-171,2006 · 20 pages, 8 figures, submitted to ApJ
arxiv created 2006/07/11 · openalex publication_date 2006/12/29 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We measure the evolution in the virial mass-to-light ratio (M 200/LB) and virial-to-stellar mass ratio (M 200/M*) for isolated ∼L* galaxies between z ∼ 1 and z ∼ 0 by combining data from the DEEP2 Galaxy Redshift Survey and the Sloan Digital Sky Survey. Utilizing the motions of satellite galaxies around isolated galaxies, we measure line-of-sight velocity dispersions and derive dark matter halo virial masses for these host galaxies. At both epochs the velocity dispersion of satellites correlates with host galaxy stellar mass, σ ∝ M*0.4+/-0.1, while the relation between satellite velocity dispersion and host galaxy B-band luminosity may grow somewhat shallower from σ ∝ LB0.6+/-0.1 at z ∼ 1 to σ ∝ LB0.4+/-0.1 at z ∼ 0. The evolution in M200/M* from z∼ 1 to z∼ 0 displays a bimodality insofar as host galaxies with stellar mass below M* ∼ 1011 h-1 Mo maintain a constant ratio (the intrinsic increase is constrained to a factor of 1.1 +/- 0.5) while host galaxies above M*∼ 1011 h-1 Mo experience a factor of 3.3 +/- 2.2 increase in their virial-to-stellar mass ratio. This result can be easily understood if galaxies below this stellar mass scale continue to form stars while star formation in galaxies above this scale is quenched and the dark matter halos of galaxies both above and below this scale grow in accordance with ACDM cosmological simulations. Host galaxies that are red in U-B color have larger satellite dispersions and hence reside on average in more massive halos than blue galaxies at both z∼ 1 and z∼ 0. The satellite population of host galaxies varies little between these epochs. The redshift and host galaxy stellar mass dependence of M200/ M* agrees qualitatively with the Millennium Run semianalytic model of galaxy formation.