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Tests for Non-Gaussian Statistics in the DMR Four-Year Sky Maps

A. Kogut·A. J. Banday·C. L. Bennett·K. Gorski·G. Hinshaw·G. F. Smoot·E. L. Wright
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Abstract

We search the high-latitude portion of the COBE Differential Microwave Radiometers (DMR) 4-year sky maps for evidence of a non-Gaussian temperature distribution in the cosmic microwave background. The genus, 3-point correlation function, and 2-point correlation function of temperature maxima and minima are all in excellent agreement with the hypothesis that the CMB anisotropy on angular scales of 7 degrees or larger represents a random-phase Gaussian field. A likelihood comparison of the DMR sky maps to a set of random-phase non-Gaussian toy models selects the exact Gaussian model as most likely. Monte Carlo simulations show that the 2-point correlation of the peaks and valleys in the maps provides the greatest discrimination among the class of models tested.

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A. Kogut, A. J. Banday, C. L. Bennett, K. Gorski, G. Hinshaw, G. F. Smoot, E. L. Wright. 1996-01-12. Tests for Non-Gaussian Statistics in the DMR Four-Year Sky Maps. https://doi.org/10.1086/310078

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