The Fraction of Quiescent Massive Galaxies in the Early Universe

A. Fontana, P. Santini, A. Grazian, L. Pentericci, F. Fiore, M. Castellano, E. Giallongo, N. Menci, S. Salimbeni, S. Cristiani, M. Nonino, E. Vanzella
0901.2898

Bottom: Fraction of "Red and Dead" galaxies (defined as SFR/stellar mass <10^-11 yr-1) as a function of redshift. Sample is selected to include only galaxies with stellar masses greater than 7x10^10 solar masses. Filled points are data, lines and shaded region refer to theoretical predictions. Upper panel: Fraction of "Quiescent galaxies" (defined as SFR/stellar mass < age of Universe at redshift of galaxy) for the same mass selected sample.