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Galaxy Luminosity Function in Groups

Hernán Muriel·Carlos A. Valotto·Diego G. Lambas
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Abstract

We compute the luminosity function of galaxies in groups. The data consists in two samples of groups of galaxies selected in distance and redshift space comprising a total number of 66 groups. The assignment of galaxies to the groups were derived from the Edinburgh-Durham Southern Galaxy Catalog, considering a limiting apparent magnitude $m_{lim}=19.4$. We find a flat faint end of the mean galaxy luminosity function in groups in contrast to the mean galaxy LF in clusters where a large relative number of faint galaxies is present. We find that a Schechter function with parameters $M^{*}\simeq -19.6\pm 0.2,$ $α\simeq -1.0\pm $ 0.2 provides a satisfactory fit to the galaxy LF of our total sample of groups in the range of absolute magnitudes $-22<M<-16$.

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Hernán Muriel, Carlos A. Valotto, Diego G. Lambas. 1998-04-28. Galaxy Luminosity Function in Groups. https://doi.org/10.1086/306262

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