Large Angular Scale Anisotropy in Cosmic Microwave Background Induced by Cosmic Strings

We simulate the anisotropy in the cosmic microwave background (CMB) induced by cosmic strings. By numerically evolving a network of cosmic strings we generate full-sky CMB temperature anisotropy maps. Based on 192 maps, we compute the anisotropy power spectrum for multipole moments 20. By comparing with the observed temperature anisotropy, we set the normalization for the cosmic string mass per unit length, obtaining G/c^2{0ex{0ex}=0ex{0ex}1. 05}-₀. ₂₀^+0. 3510^-6, which is consistent with all other observational constraints on cosmic strings. We demonstrate that the anisotropy pattern is consistent with a Gaussian random field on large angular scales.