Key points are not available for this paper at this time.
The spectral properties of more than 400 CFRS galaxies and their changes over the redshift interval 0 ≤ z ≤ 1.3 are investigated. Emission line intensities and equivalent widths for accessible lines have been measured, as well as continuum color indices based on 200˚A wide spectral regions. Within the CFRS sample, the comoving fraction of galaxies with significant emission lines (W0(OII) 15˚A) increases from ∼ 13% locally to over 50 % at z 0.5. The fraction of luminous ( MB -20) quiescent galaxies (those without OII 3727 emission) decreases with redshift from 53 % at z = 0.3 to 23 % at z0.5, the latter fraction being similar to that of early type galaxies at that redshift. There is considerable evidence in the data presented here that star formation increases from z = 0 to z 0.5 in disk galaxies. However, the absence of extremely blue colors and the presence of significant Balmer absorption suggests that the star formation is primarily taking place over long periods of time, rather than in short-duration, high-amplitude “bursts”. There are several indications that the average metallicity and dust opacity were
Hammer et al. (1997) studied this question.