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arXiv · 1407.1470

Supervoid Origin of the Cold Spot in the Cosmic Microwave Background

András Kovács·István Szapudi·Benjamin R. Granett·Zsolt Frei·Joseph Silk·Will Burgett·Shaun Cole·Peter W. Draper·Daniel J. Farrow·Nicholas Kaiser·Eugene A. Magnier·Nigel Metcalfe·Jeffrey S. Morgan·Paul Price·John Tonry·Richard Wainscoat
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Abstract

We use a WISE-2MASS-Pan-STARRS1 galaxy catalog to search for a supervoid in the direction of the Cosmic Microwave Background Cold Spot. We obtain photometric redshifts using our multicolor data set to create a tomographic map of the galaxy distribution. The radial density profile centred on the Cold Spot shows a large low density region, extending over 10's of degrees. Motivated by previous Cosmic Microwave Background results, we test for underdensities within two angular radii, $5^\circ$, and $15^\circ$. Our data, combined with an earlier measurement by Granett et al 2010, are consistent with a large $R_{\rm void}=(192 \pm 15)h^{-1} Mpc $ $(2σ)$ supervoid with $δ\simeq -0.13 \pm 0.03$ centered at $z=0.22\pm0.01$. Such a supervoid, constituting a $\sim3.5 σ$ fluctuation in the $ΛCDM$ model, is a plausible cause for the Cold Spot.

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András Kovács, István Szapudi, Benjamin R. Granett, Zsolt Frei, Joseph Silk, Will Burgett, Shaun Cole, Peter W. Draper, Daniel J. Farrow, Nicholas Kaiser, Eugene A. Magnier, Nigel Metcalfe, Jeffrey S. Morgan, Paul Price, John Tonry, Richard Wainscoat. 2014-07-06. Supervoid Origin of the Cold Spot in the Cosmic Microwave Background. https://arxiv.org/abs/1407.1470

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