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Limits on f_NL parameters from WMAP 3yr data

Paolo Creminelli·Leonardo Senatore·Matias Zaldarriaga·Max Tegmark
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Abstract

We analyze the 3-year WMAP data and look for a deviation from Gaussianity in the form of a 3-point function that has either of the two theoretically motivated shapes: local and equilateral. There is no evidence of departure from Gaussianity and the analysis gives the presently tightest bounds on the parameters f_ NL^local and f_NL^equil., which define the amplitude of respectively the local and the equilateral non-Gaussianity: -36 < f_NL^local < 100, -256 < f_NL^equil. < 332 at 95% C.L.

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Paolo Creminelli, Leonardo Senatore, Matias Zaldarriaga, Max Tegmark. 2007-03-05. Limits on f_NL parameters from WMAP 3yr data. https://doi.org/10.1088/1475-7516%2F2007%2F03%2F005

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