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arXiv · 1510.09076

On the void explanation of the Cold Spot

A. Marcos-Caballero·R. Fernández-Cobos·E. Martínez-González·P. Vielva
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Abstract

The integrated Sachs-Wolfe (ISW) contribution induced on the cosmic microwave background by the presence of a supervoid as the one detected by Szapudi et al. (2015) is reviewed in this letter in order to check whether it could explain the Cold Spot (CS) anomaly. Two different models, previously used for the same purpose, are considered to describe the matter density profile of the void: a top hat function and a compensated profile produced by a Gaussian potential. The analysis shows that, even enabling ellipticity changes or different values for the dark-energy equation of state parameter $ω$, the ISW contribution due to the presence of the void does not reproduce the properties of the CS. Finally, the probability of alignment between the void and the CS is also questioned as an argument in favor of a physical connection between these two phenomena.

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A. Marcos-Caballero, R. Fernández-Cobos, E. Martínez-González, P. Vielva. 2016-04-14. On the void explanation of the Cold Spot. https://doi.org/10.1093/mnrasl%2Fslw063

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