2003/11/10 by Kyu-Hyun Chae, Shude Mao · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Cosmology and Gravitation Theories #Dispersion (optics) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gravitational lens #Lens (geology) #Quasar #Redshift #Sky #Velocity dispersion #astro-ph
paper · pdf · doi:10.1086/381247
published as Astrophys.J. 599 (2003) L61-L64 · 10 pages (preprint format), 2 figures, ApJL in press (December 20th issue)
arxiv created 2003/11/10 · openalex publication_date 2003/12/02 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We use gravitational lenses from the Cosmic Lens All-Sky Survey to constrain the evolution of galaxies since redshift z ~ 1 in the current Λ cold dark matter cosmology. This constraint is unique as it is based on a mass-selected lens sample of galaxies. Our method of statistical analysis is the same as that done in recent work by K.-H. Chae. We parameterize the early-type number density evolution in the form of (1 + z ) and the velocity dispersion in the form of (1 + z ) . We find that ν n = -0.11 (1 σ) if we assume ν v = 0, implying that the number density of early-type galaxies is within 50%-164% of the present-day value at redshift z = 1. Allowing the velocity dispersion to evolve, we find that ν v = -0.4 (1 σ), indicating that the velocity dispersion must be within 57%-107% of the present-day value at z = 1. These results are consistent with the early formation and passive evolution of early-type galaxies. More stringent limits from lensing can be obtained from future large lens surveys and by using very high redshift quasars ( z ≳ 5) such as those found from the Sloan Digital Sky Survey.