2006ApJ...650...18T

We present the evolution of the luminosity-size and stellar mass-size relations of luminous (L_V≳3.4x10¹⁰ h^–2₇₀L_☉) and massive (M_*≳3x10¹⁰ h^–2₇₀M_☉) galaxies in the last ∼11 Gyr. We use very deep near-infrared images of the Hubble Deep Field-South and the MS 1054-03 field in the J_s, H, and K_s bands from FIRES to retrieve the sizes in the optical rest frame for galaxies with z>1. We combine our results with those from GEMS at 0.2<z<1 and SDSS at z∼0.1 to achieve a comprehensive picture of the optical rest-frame size evolution from z=0 to 3. Galaxies are differentiated according to their light concentration using the Sérsic index n. For less concentrated objects, the galaxies at a given luminosity were typically ∼3±0.5 (±2 σ) times smaller at z∼2.5 than those we see today. The stellar mass-size relation has evolved less: the mean size at a given stellar mass was ∼2±0.5 times smaller at z∼2.5, evolving proportionally to (1+z)^{–0.40±0.06}. Simple scaling relations between dark matter halos and baryons in a hierarchical cosmogony predict a stronger (although consistent within the error bars) than observed evolution of the stellar mass-size relation. The observed luminosity-size evolution out to z∼2.5 matches well recent infall model predictions for Milky Way-type objects. For low-n galaxies, the evolution of the stellar mass-size relation would follow naturally if the individual galaxies grow inside out. For highly concentrated objects, the situation is as follows: at a given luminosity, these galaxies were ∼2.7±1.1 times smaller at z∼2.5 (or, put differently, were typically ∼2.2±0.7 mag brighter at a given size than they are today), and at a given stellar mass the size has evolved proportionally to (1+z)^{–0.45±0.10}.