The Imperial IRAS-FSC Redshift Catalogue: Luminosity functions, evolution and galaxy bias

Abstract

We present the luminosity function and selection function of 60 μm galaxies selected from the Imperial IRAS-FSC Redshift Catalogue. Three methods, including the 1/Vmax and the parametric and non-parametric maximum-likelihood estimators, are used and the results agree well with each other. A density evolution ∝ (1 + z)3.4±0.9 or a luminosity evolution ∝ exp(1.7 tL/τ), where tL is the look-back time, is detected in the full sample in the redshift range [0.02, 0.1], consistent with previous analyses. Of the four infrared subpopulations, cirrus-type galaxies and M82-type starbursts show similar evolutionary trends, galaxies with significant active galactic nucleus contributions show stronger positive evolution and Arp 220-type starbursts exhibit strong negative evolution. The dominant subpopulation changes from cirrus-type galaxies to M82-type starbursts at log10(L60/L⊙) ≈ 10.3. In the second half of the paper, we derive the projected two-point spatial correlation function for galaxies of different infrared template types. The mean relative bias between cirrus-type galaxies and M82-type starbursts, which correspond to quiescent galaxies with optically thin interstellar dust and actively star-forming galaxies, respectively, is calculated to be b cirrus/bM82 = 1.25 ± 0.07. The relation between the current star formation rate (SFR) in star-forming galaxies and environment is investigated by looking at the dependence of clustering on infrared luminosity. We found that M82-type actively star-forming galaxies show stronger clustering as infrared luminosity/SFR increases. The correlation between the clustering strength and SFR in the local Universe seems to echo the basic trend seen in star-forming galaxies in the Great Observatories Origins Deep Survey fields (at z ∼ 1). © 2009 RAS.