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CMB Anisotropies at Second-Order II: Analytical Approach

Nicola Bartolo·Sabino Matarrese·Antonio Riotto
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Abstract

We provide an analytical approach to the second-order Cosmic Microwave Background (CMB) anisotropies generated by the non-linear dynamics taking place at last scattering. We study the acoustic oscillations of the photon-baryon fluid in the tight coupling limit and we extend at second-order the Meszaros effect. We allow for a generic set of initial conditions due to primordial non-Gaussianity and we compute all the additional contributions arising at recombination. Our results are useful to provide the full second-order radiation transfer function at all scales necessary for establishing the level of non-Gaussianity in the CMB.

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Nicola Bartolo, Sabino Matarrese, Antonio Riotto. 2007-01-30. CMB Anisotropies at Second-Order II: Analytical Approach. https://doi.org/10.1088/1475-7516%2F2007%2F01%2F019

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