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Strong Angular Clustering of Very Blue Galaxies: Evidence of a Low Redshift Population

Stephen D. Landy·Alexander S. Szalay·David C. Koo
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Abstract

We have studied galaxy two-point angular correlations as a function of color using 4-m plate photometry in two independent fields. Each field consists of over 2900 galaxies with magnitudes 20<B_J <23.5 in an area of approximately 750 arcmin^2 . We find that the autocorrelation amplitude of the bluest 15% of galaxies is surprisingly strong, with a relative increase in clustering amplitude of a factor of 6 over that of the complete data set, while exhibiting a power law slope consistent with the canonical value of -0.8. These very blue galaxies are also found to be weakly correlated with galaxies of median color and marginally anti-correlated with the reddest subset. These correlation properties are incompatible with existing simple models of the galaxy distribution; they suggest that a significant fraction, more than 50%, of these very blue galaxies are a faint population which lie at nearby redshifts z<0.3.

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Stephen D. Landy, Alexander S. Szalay, David C. Koo. 1995-11-28. Strong Angular Clustering of Very Blue Galaxies: Evidence of a Low Redshift Population. https://doi.org/10.1086/176954

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