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arXiv · astro-ph/9510131

Colors, Luminosity Function and Counts of Galaxies

P. Saracco·G. Chincarini·A. Iovino
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Abstract

Standard models for deep galaxy counts are based on luminosity functions (LF) with relatively flat faint end ($α\sim-1.0$). Galaxy counts in the B--band exceed the prediction of such models by a factor of 2 to more than 5, forcing the introduction of strong luminosity and/or density evolution. Recently Marzke et al. (1994a) using the CfA redshift survey sample find that the number of galaxies in the range $-16 <2.5$ for dwarf galaxies, we reproduce well also the observed $K$--band deep galaxy counts. This assumption is supported by the strong correlation we found between $B-K$ color of galaxies and their infrared absolute magnitude: galaxies become bluer with decreasing luminosity.

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P. Saracco, G. Chincarini, A. Iovino. 1996-07-25. Colors, Luminosity Function and Counts of Galaxies. https://doi.org/10.1093/mnras%2F283.3.865

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