The Canada-France-Hawaii telescope legacy survey:: The morphology-density relation of galaxies out to z∼1

We study the relationships between galaxy total luminosity (M-g'), morphology, color, and environment as a g function of redshift. We use a magnitude- limited sample of 65,624 galaxies in the redshift range taken 0 < z < 1.3 from one of the Canada- France- Hawaii Telescope Legacy Survey Deep Fields. We parameterize galaxy 1 degrees x1 degrees morphology according to the Sersic index n, taking n > 2 to be " bulge- dominated" and to be " disk-dominated." Our n > 2 number fractions at z + 0.1 agree well with those based on Sloan Digital Sky Survey galaxies. We find that the n > 2 galaxy number fraction is constant with redshift in the field. However, for overdense environments, this fraction is larger and increases toward lower redshifts, higher densities, and higher luminosities. Rest- frame color- magnitude diagrams show that the color distribution is bimodal out to our redshift limit of z similar to 1 with a prominent red sequence of galaxies at and a large blue- peak dominance at 0.8 < z < 1. We use this bimodality to define a red fraction as the fraction of galaxies having a rest- frame color u* - g' > 1. For all environments, this fraction increases toward lower redshifts and higher luminosities. The red fraction within cluster- like regions changes 60% faster with redshift as compared to the field for galaxies with M-g' < -19.5. Using, for the first time, observations across many cluster- field interfaces distributed over a single, large volume, we trace the large- scale morphology- density relation and the Butcher- Oemler effect over a period of almost 8 Gyr.