Population synthesis models for late buildup of the red sequence

作者：Harker Justin J^*; Schiavon Ricardo P; Weiner Benjamin J; Faber S M

来源：Astrophysical Journal, 2006, 647(2): L103-L106.

DOI：10.1086/507581

• galaxies : evolution
• galaxies : formation
• galaxies : high-redshift
• galaxies : stellar content

We present population synthesis models designed to represent the star formation histories of L-* red sequence galaxies ( RSGs). Earlier work has shown that single- burst stellar populations (SSPs) are unable to match Balmer line strengths simultaneously at high and low redshift. We therefore consider alternative star formation histories in which RSGs contain intermediate-aged stars even at late epochs. The models are compared to Balmer H delta(F) absorption strengths U - B color data, and the number density of red sequence galaxies from z = 1 to z = 0 We find that quenched models, models of constant star formation histories truncated at regularly spaced intervals, average to an RSG population that matches the data well, showing slow evolution in color and Balmer line strength and a rise in number density by a factor of a few after z =1. The data are best fit by a turn-on of quenching at redshifts z = 1.5-2.

• 出版日期2006-8-20