The Angular Clustering of Galaxy Pairs

We identify close pairs of galaxies from 278 deg2 of Sloan Digital Sky Survey commissioning imaging data. The pairs are drawn from a sample of 330,041 galaxies with 18 < r* < 20. We determine the angular correlation function of galaxy pairs and find it to be stronger than the correlation function of single galaxies by a factor of 2.9 ± 0.4. The two correlation functions have the same logarithmic slope of 0.77. We invert Limber's equation to estimate the three-dimensional correlation functions; we find clustering lengths of r0 = 4.2 ± 0.4 h-1 Mpc for galaxies and 7.8 ± 0.7 h-1 Mpc for galaxy pairs. These results agree well with the global richness dependence of the correlation functions of galaxy systems.