2002/08/12 by J. P. Willis, P. C. Hewett, S. J. Warren +2
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Luminosity #Luminosity function #Luminous infrared galaxy #Physics #Redshift #Star formation #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.2002.05970.x
published as Mon.Not.Roy.Astron.Soc.337:953,2002 · 16 pages, 10 figures, accepted for publication in MNRAS. Previous submission contained mn.sty - now removed
arxiv created 2002/08/12 · openalex publication_date 2002/12/11 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We present a combined photometric and spectroscopic analysis of the star formation history and space density of a sample of 485 luminous, MV− 5 log h < −20.5, field early-type galaxies at redshifts 0.3 ≲z≲ 0.6. The observed bJori colours as a function of redshift, mean absorption-line strengths and [O ii]λ3727 emission properties are used to constrain the star formation history of the galaxies. The mean star formation history of the early-type galaxy sample is consistent with an old (zf > 1), passively evolving luminosity-weighted stellar population. 21 per cent of the sample possess detectable [O ii]λ3727 emission consistent with a low level (≲1 M⊙ yr−1) of on-going star formation. Parametric and non-parametric estimates of the space density of the sample are derived. The integrated luminosity density at z≃ 0.4, allowing only for passive luminosity evolution, is in excellent agreement with the local, (〈z〉= 0.1), luminosity density of early-type galaxies. Overall, the sample properties are consistent with a galaxy formation scenario in which the majority of luminous field early-type galaxies formed at redshifts z > 1 and have largely evolved passively since the formation epoch.