The goal of this work is to study the evolution of high-redshift (z ≥ 1.4) quiescent galaxies over an effective area of ~ 1.7 deg^2 in the COSMOS field. Galaxies have been divided according to their star formation activity and the evolution of the different populations, in particular of the quiescent galaxies, has been investigated in detail. We have studied an IRAC (ma_( 3.6 μm) 2.5 (log_ρ[M_⊙ Mpc^(−3)]~ 6), meaning that efficient star formation had to take place before that time
