Cosmic Microwave Background Anisotropies from Scaling Seeds: Fit to Observational Data

Abstract

We compute cosmic microwave background angular power spectra for scaling seed models of structure formation. A generic parametrization of the energy momentum tensor of the seeds is employed. We concentrate on two regions of parameter space inspired by global topological defects: $O(4)$ texture models and the large- $N$ limit of $O(N)$ models. We use ${\ensuremath{\chi}}^{2}$ fitting to compare these models to recent flat-band power measurements of the cosmic microwave background. Only scalar perturbations are considered.