DOPPLER PEAKS IN THE ANGULAR POWER SPECTRUM OF THE COSMIC MICROWAVE BACKGROUND - A FINGERPRINT OF TOPOLOGICAL DEFECTS

The Doppler peaks (Sacharov peaks) in the angular power spectrum of th e cosmic microwave background anisotropies are due mainly to coherent oscillations in the baryon radiation plasma before recombination. Here we present a calculation of the Doppler peaks for perturbations induc ed by global textures and cold dark matter. We find that the height of the first Doppler peak is smaller than in standard cold dark matter m odels, and that its position is shifted to l similar to 350. We believ e that our analysis can be easily extended to other types of global to pological defects and general global scalar fields.