Search for Cosmic Strings in Cosmic Microwave Background Anisotropies

Abstract

We have searched the first-year Wilkinson Microwave Anisotropy Probe (WMAP) W-band CMB anisotropy map for evidence of cosmic strings. We set a limit on the dimensionless string parameter δ of δ = 8πGμγβ < 2.9 × 10-5 for the statistical search for a significant number of strings in the map. We also set a limit using the uniform-distribution-of-strings model in the WMAP data with δ = 8πGμγβ < 7.3 × 10-5 at the 95% confidence level (CL). The pattern search technique we developed in this paper set a limit δ = 8πGμγβ < 1.5 × 10-5 at the 95% CL, which corresponds to a limit on the symmetry-breaking energy scale of 1016 GeV/γβ.