# Scale-dependent non-Gaussianities in the WMAP data as identified by using surrogates and scaling indices

@article{Raeth2010ScaledependentNI, title={Scale-dependent non-Gaussianities in the WMAP data as identified by using surrogates and scaling indices}, author={Christoph W. Raeth and A. J. Banday and Gregor Johannes Rossmanith and Heike Modest and Robert Suetterlin and Krzysztof M. Gorski and Jacques Delabrouille and Gregor Eugen Morfill}, journal={Monthly Notices of the Royal Astronomical Society}, year={2010}, volume={415}, pages={2205-2214} }

We present a model-independent investigation of the Wilkinson Microwave Anisotropy Probe (WMAP) data with respect to scale-independent and scale-dependent non-Gaussianities (NGs). To this end, we employ the method of constrained randomization. For generating so-called surrogate maps a well-specified shuffling scheme is applied to the Fourier phases of the original data, which allows us to test for the presence of higher order correlations (HOCs) also and especially on well-defined scales. Using…

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