2004/03/31 by Raul Jimenez, Raúl Jiménez, B. Panter +3 · 5 citations
Computer Science · Physics and Astronomy · #Astronomy and Astrophysical Research #Galaxies: Formation, Evolution, Phenomena #Gaussian Processes and Bayesian Inference #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2004.08469.x
published as Mon.Not.Roy.Astron.Soc. 356 (2005) 495-501 · Replaced to match accepted version in MNRAS
arxiv created 2004/10/04 · openalex publication_date 2004/12/21 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Using the spectroscopic sample of the Sloan Digital Sky Survey Data Release 1 (SDSS DR1), we measure how gas was transformed into stars as a function of time and stellar mass: the baryonic conversion tree (BCT). There is a clear correlation between early star formation activity and present-day stellar mass: the more massive galaxies have formed approximately 80 per cent of their stars at z > 1, while for the less massive ones the value is only approximately 20 per cent. By comparing the BCT with the dark matter merger tree, we find indications that star formation efficiency at z > 1 had to be approximately a factor of two higher than today (∼10 per cent) in galaxies with present-day stellar mass larger than 2 × 1011M⊙, if this early star formation occurred in the main progenitor. Therefore, the λ cold dark matter (LCDM) paradigm can accommodate a large number of red objects. On the other hand, in galaxies with present-day stellar mass less than 1011M⊙, efficient star formation seems to have been triggered at z∼ 0.2. We show that there is a characteristic mass (M*∼ 1010M⊙) for feedback efficiency (or lack of star formation). For galaxies with masses lower than this, feedback (or star formation suppression) is very efficient while for higher masses it is not. The BCT, determined here for the first time, should be an important observable with which to confront theoretical models of galaxy formation.