Large-Scale Clustering of Galaxies with Massive Dark Halos. I. General Structure, Two-Point Correlations, and Binaries

N-body simulations of large-scale clustering of galaxies with massive dark halos are performed and compared to models where galaxies are treated as point masses. Simulations with 800 galaxies in both a flat (Ω = 1.0) and open (Ω_f = 0.15) universe are evolved from a Poisson initial density distribution in a periodic comoving cube of final length 63 Mpc. In the dark matter models, two "species" of particles are used, galactic systems are comprised initially of a single "luminous" particle centered in an extended halo of 25 "dark" particles. Ninety percent of the total mass is contained in the halos, which are not "locked" to a given galaxy. The most significant observable effects of dark halos are the lowering of galaxy pair peculiar velocities, particularly on scales r < 500 kpc, the enhancement of small-scale clustering through dynamical friction, and the suppression or delay of clustering on 1 - 5 Mpc scales.