http://arxiv.org/abs/1410.5854
We present the redshift evolution of the high-mass end of the ^{0.55}i-band Red Sequence Luminosity Function (RS LF) within the redshift range 0.52<z<0.65, obtained from the DR10 BOSS CMASS sample, which comprises ~ 600,000 galaxies. We have developed an analytical method based on an unbinned maximum likelihood approach for deconvolving the observed CMASS distribution from photometric errors and accounting for selection effects. This procedure requires modeling the covariance matrix for the i-band magnitude, g-r color and r-i color using Stripe 82 multi-epoch data. The error-deconvolved intrinsic RS distribution is consistent with a single point in the color-color plane, which implies that the great majority of the observed scatter is due to photometric errors. We estimate that RS completeness is ~0.80-0.85 at z\geq0.52 in the CMASS sample, dropping drastically below that redshift. Approximately 37% of all objects in the CMASS sample belong intrinsically to the blue cloud. Within the redshift and absolute magnitude range considered (^{0.55}M_i \lesssim -22), the evolution of the RS LF is consistent with a Schechter Function of \Phi_* = (6.693\pm0.042) x 10^{-4} Mpc^{-3} mag^{-1}, passively fading at a rate of 1.180\pm0.001 mag per unit redshift. This result implies an age of ~4-5 Gyr at z=0.70, and a formation redshift of z=2-3, for the LRG population, independently of the SPS model used. As for the intrinsic RS colors, FSPS models within a grid covering a wide range of metallicities and dust contents tend to predict a milder evolution as compared to the observations. The best agreement seems to be found for solar-metallicity, dust-free FSPS models with ages greater than ~5 Gyr, which would be consistent with our fading rate results. The Maraston et al. (2009) passive LRG model provides an excellent match to the color-redshift trend, implying an age of ~3-4 Gyr at z=0.70. [ABRIDGED]
A. Montero-Dorta, A. Bolton, J. Brownstein, et. al.
Thu, 23 Oct 14
47/60
Comments: 29 pages, 22 figures, submitted to MNRAS