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Non-Gaussian signature induced by the SZ effect of galaxy clusters

N. Aghanim·O. Forni
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Abstract

We apply statistical tests, based on the study of thecoefficients in a wavelet decomposition, to a cosmological signal: the Cosmic Microwave Background (CMB) anisotropies. The latter represent the superposition of primary anisotropy imprints of the initial density perturbations and secondary anisotropies due to photon interactions after recombination. In an inflationary scenario with Gaussian distributed fluctuations, we study the statistical signature of the secondary effects. More specifically, we investigate the dominant effects arising from the Sunyaev-Zel'dovich effect of galaxy clusters. Our study predicts the non-Gaussian signature of these secondary anisotropies and its detectability in the context of the future CMB satellite Planck Surveyor.

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N. Aghanim, O. Forni. 2000-03-17. Non-Gaussian signature induced by the SZ effect of galaxy clusters. https://arxiv.org/abs/astro-ph/0003256

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