Abstract
We have developed a model for the photoionization suppression of galaxy formation resulting from the reionization of the Universe. This suppression is incorporated into the galaxy formation model of Cole et al. (2000), producing a fully self-consistent model for the evolution of the IGM and the galaxy population. We study in detail the consequences for the population of galaxies at z = 0, and focus on the galaxies seen in the Local Group. The abundance of Local Group satellites is significantly reduced, predicting numbers comparable to those observed. Photoionization suppression does not produce a strong environmental variation in the galaxy luminosity function, in contrast to observations. Finally, we demonstrate that the predicted abundance of substructure in cold dark matter halos is consistent with the thinness of the Milky Way disk.
