The Complete Bispectrum of COBE-DMR Four Year Maps

H. B. Sandvik; J. Magueijo

doi:10.1046/j.1365-8711.2001.04384.x

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arXiv · astro-ph/0010395

The Complete Bispectrum of COBE-DMR Four Year Maps

H. B. Sandvik·J. Magueijo

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Abstract

We extend a previous bispectrum analysis of the COBE-DMR 4 year maps, allowing for the presence of correlations between all possible angular scales. We find that the non-Gaussian signal found earlier for bispectrum components including adjacent modes does not extend to triplets of modes with larger separations. Indeed for all separations $Δ\ell >1$ we find that the COBE-DMR data is very Gaussian. The implication seems to be that the previously detected non-Gaussian scale-scale correlation falls off very quickly with mode separation.

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H. B. Sandvik, J. Magueijo. 2000-10-19. The Complete Bispectrum of COBE-DMR Four Year Maps. https://doi.org/10.1046/j.1365-8711.2001.04384.x

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