Article

# Limits on Primordial Non-Gaussianity from Minkowski Functionals of the WMAP Temperature Anisotropies

02/2008; DOI:doi:10.1111/j.1365-2966.2008.13674.x
Source: arXiv

ABSTRACT We present an analysis of the Minkowski Functionals (MFs) describing the WMAP three-year temperature maps to place limits on possible levels of primordial non-Gaussianity. In particular, we apply perturbative formulae for the MFs to give constraints on the usual non-linear coupling constant fNL. The theoretical predictions are found to agree with the MFs of simulated CMB maps including the full effects of radiative transfer. The agreement is also very good even when the simulation maps include various observational artifacts, including the pixel window function, beam smearing, inhomogeneous noise and the survey mask. We find accordingly that these analytical formulae can be applied directly to observational measurements of fNL without relying on non-Gaussian simulations. Considering the bin-to-bin covariance of the MFs in WMAP in a chi-square analysis, we find that the primordial non-Gaussianity parameter is constrained to lie in the range -70<fNL<91 at 95% C.L. using the Q+V+W co-added maps. Comment: 9 pages, 4 figures, accpeted for publication in MNRAS

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Available from
11 Jan 2013

### Keywords

analytical formulae

beam smearing

chi-square analysis

full effects

inhomogeneous noise

MFs

Minkowski Functionals

non-Gaussian simulations

observational measurements

perturbative formulae

pixel window function

possible levels

primordial non-Gaussianity

primordial non-Gaussianity parameter