2016MNRAS.461.1131M

We have developed an analytical method based on forward-modelling techniques to characterize the high-mass end of the red sequence (RS) galaxy population at redshift z ∼ 0.55, from the DR10 BOSS (Baryon Oscillation Spectroscopic Survey) CMASS spectroscopic sample, which comprises ∼600 000 galaxies. The method, which follows an unbinned maximum likelihood approach, allows the deconvolution of the intrinsic CMASS colour-colour-magnitude distributions from photometric errors and selection effects. This procedure requires modelling the covariance matrix for the i-band magnitude, g - r colour and r - i colour using Stripe 82 multi-epoch data. Our results indicate that the error-deconvolved intrinsic RS distribution is consistent, within the photometric uncertainties, with a single point (<0.05 mag) in the colour-colour plane at fixed magnitude, for a narrow redshift slice. We have computed the high-mass end (^0.55M_i <= -22) of the ^0.55i-band RS luminosity function (RS LF) in several redshift slices within the redshift range 0.52 < z < 0.63. In this narrow redshift range, the evolution of the RS LF is consistent, within the uncertainties in the modelling, with a passively evolving model with Φ_*=(7.248±0.204) x 10^- 4^ Mpc^–3 mag^–1, fading at a rate of 1.5±0.4 mag per unit redshift. We report RS completeness as a function of magnitude and redshift in the CMASS sample, which will facilitate a variety of galaxy-evolution and clustering studies using BOSS. Our forward-modelling method lays the foundations for future studies using other dark-energy surveys like the Extended Baryon Oscillation Spectroscopic Survey or the Dark Energy Spectroscopic Instrument, which are affected by the same type of photometric blurring/selection effects.