The complete bispectrum of COBE-DMR Four Year Maps

نویسندگان

  • H̊avard B. Sandvik
  • João Magueijo
چکیده

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 ∆l > 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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تاریخ انتشار 2008