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arXiv · 1202.1478

On the linear term correction for needlets/wavelets non-Gaussianity estimators

Simona Donzelli·Frode K. Hansen·Michele Liguori·Domenico Marinucci·Sabino Matarrese
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Abstract

We derive the linear correction term for needlet and wavelet estimators of the bispectrum and the non-linearity parameter fNL on cosmic microwave background radiation data. We show that on masked WMAP-like data with anisotropic noise, the error bars improve by 10-20% and almost reach the optimal error bars obtained with the KSW estimator (Komatsu et al 2005). In the limit of full-sky and isotropic noise, this term vanishes. We apply needlet and wavelet estimators to the WMAP 7-year data and obtain our best estimate fNL=37.5 \pm 21.8.

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Simona Donzelli, Frode K. Hansen, Michele Liguori, Domenico Marinucci, Sabino Matarrese. 2012-02-07. On the linear term correction for needlets/wavelets non-Gaussianity estimators. https://doi.org/10.1088/0004-637x/755/1/19

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