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Microwave sky and the local Rees-Sciama effect

Aleksandar Rakic·Syksy Rasanen·Dominik J. Schwarz
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Abstract

The microwave sky shows unexpected features at the largest angular scales, among them the alignments of the dipole, quadrupole and octopole. Motivated by recent X-ray cluster studies, we investigate the possibility that local structures at the 100 h^(-1) Mpc scale could be responsible for such correlations. These structures give rise to a local Rees-Sciama contribution to the microwave sky that may amount to Delta T/T ~ 10^(-5) at the largest angular scales. We model local structures by a spherical overdensity (Lemaitre-Tolman-Bondi model) and assume that the Local Group is falling toward the centre. We superimpose the local Rees-Sciama effect on a statistically isotropic, gaussian sky. As expected we find alignments among low multipoles, but a closer look reveals that they do not agree with the type of correlations revealed by the data.

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Aleksandar Rakic, Syksy Rasanen, Dominik J. Schwarz. 2006-04-21. Microwave sky and the local Rees-Sciama effect. https://doi.org/10.1111/j.1745-3933.2006.00167.x

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