The angular power spectrum of galaxies from early Sloan Digital Sky Survey Data

We compute the angular power spectrum C-l from 1.5 million galaxies in early Sloan Digital Sky Survey (SDSS) data on large angular scales, l less than or similar to 600. The data set covers about 160 deg(2), with a characteristic depth on the order of 1 h(-1) Gpc in the faintest (21 < r* < 22) of our four magnitude bins. Cosmological interpretations of these results are presented in a companion paper by Dodelson and coworkers. The data in all four magnitude bins are consistent with a simple at concordance model with nonlinear evolution and linear bias factors on the order of unity. Nonlinear evolution is particularly evident for the brightest galaxies. A series of tests suggests that systematic errors related to seeing, reddening, etc. are negligible, which bodes well for the 60-fold larger sample that the SDSS is currently collecting. Uncorrelated error bars and well-behaved window functions make our measurements a convenient starting point for cosmological model fitting.