Luminosity and Clustering of Galaxies Selected by Ew (hα)
نویسنده
چکیده
We study the luminosity function and clustering properties of subsamples of local galaxies selected from the Stromlo-APM survey by the rest-frame equivalent width (EW) of the Hα emission line. The bJ luminosity function of star-forming galaxies has a significantly steeper faint-end slope than that for quiescent galaxies: the majority of sub-L galaxies are currently undergoing significant star formation. Emission line galaxies are less strongly clustered, both amongst themselves, and with the general galaxy population, than quiescent galaxies. Thus as well as being less luminous, star-forming galaxies also inhabit lower-density regions of the Universe than quiescent galaxies.
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