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Large Angular Scale CMB Anisotropy Induced by Cosmic Strings

B. Allen·R. R. Caldwell·E. P. S. Shellard·A. Stebbins·S. Veeraraghavan
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Abstract

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 $\ell \le 20$. By comparing with the observed temperature anisotropy, we set the normalization for the cosmic string mass-per-unit-length $μ$, obtaining $Gμ/c^2=1.05 {}^{+0.35}_{-0.20} \times10^{-6}$, 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.

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B. Allen, R. R. Caldwell, E. P. S. Shellard, A. Stebbins, S. Veeraraghavan. 1996-09-05. Large Angular Scale CMB Anisotropy Induced by Cosmic Strings. https://doi.org/10.1103/physrevlett.77.3061

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