Globular Cluster Systems and the Missing Satellite Problem: Implications for Cold Dark Matter Models

We analyze the metallicity distributions of globular clusters belonging to 28early-type galaxies in the survey of Kundu & Whitmore (2001). A Monte Carloalgorithm which simulates the chemical evolution of galaxies that growhierarchically via dissipationless mergers is used to determine the mostprobable protogalactic mass function for each galaxy. Contrary to the claims ofKundu & Whitmore, we find that the observed metallicity distributions are inclose agreement with the predictions of such hierarchical formation models. Themass spectrum of protogalactic fragments for the galaxies in our sample has apower-law behavior, with an exponent of roughly -2. This spectrum isindistinguishable from the mass spectrum of dark matter halos predicted by colddark matter models for structure formation. We argue that these protogalacticfragments, the likely sites of globular cluster formation in the earlyuniverse, are the disrupted remains of the "missing" satellite galaxiespredicted by cold dark matter models. Our findings suggest that the solution tothe missing satellite problem is through the suppression of gas accretion inlow-mass halos after reionization, or via self-interacting dark matter, andargue against models with suppressed small-scale power or warm dark matter.Comment: 28 pages, 19 postscript figures. Accepted for publication in the Astrophysical Journa