TILTED COLD DARK-MATTER MODELS CONFRONT THE COSMIC MICROWAVE BACKGROUND AND THE GALAXY PECULIAR VELOCITY-FIELD

We study tilted cold dark matter (CDM) models, that is OMEGA0 = 1 mode ls with a primordial spectral index n less than or similar to 1. We te st these models against three experiments on the cosmic microwave back ground anisotropy at 7', 3-degrees, and 6-degrees, and against measure ments of galaxy peculiar velocities on large scales. These observation s together suggest that the whole class of tilted CDM models with n le ss-than-or-equal-to 1 can be ruled out, for any value of the biasing p arameter b.