ar X iv : a st ro - p h / 97 12 24 4 v 1 1 8 D ec 1 99 7 Results on Galaxy Evolution from the CNOC 2 Field Galaxy Redshift Survey
نویسندگان
چکیده
The CNOC2 Field Galaxy Redshift Survey presently contains some 5000 galaxy redshifts, plus extensive UBgRI photometry, and is the largest galaxy sample at moderate redshifts 0.1 < z < 0.6. Here we present some preliminary results on the galaxy luminosity function (LF) and its redshift evolution, using a sample of R < 21.5 CNOC2 galaxies, subdivided into early, intermediate, and late types based on their B − R colors relative to non-evolving galaxy models. We find a significant steep-ening in the faint-end slope α of the LF as one proceeds from early to late types. Also, for all galaxy types we find a rate of M * evolution consistent with that from passively evolving galaxy models. Finally, late-type galaxies show positive density evolution with redshift, in contrast to negative or no density evolution for earlier types.
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