2001/07/06 by Sergei F. Shandarin, S. F. Shandarin, Shandarin, Sergei F. +6
Computer Science · Earth and Planetary Sciences · Physics and Astronomy · #Astrophysics (astro-ph) #FOS: Physical sciences #Geochemistry and Geologic Mapping #Geological Modeling and Analysis #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0107136
21 pages, 8 figures, 2 tables. 2002, ApJS, 141, accepted
openalex publication_date 2001/07/06 · arxiv created 2002/06/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We discuss the tests of nonGaussianity in CMB maps using morphological statistics known as Minkowski functionals. As an example we test degree-scale cosmic microwave background (CMB) anisotropy for Gaussianity by studying the \qmask map that was obtained from combining the QMAP and Saskatoon data. We compute seven morphological functions Mi(\dt), i=1,...,7: six \mf and the number of regions Nc at a hundred \dt levels. We also introduce a new parameterization of the morphological functions Mi(A) in terms of the total area A of the excursion set. We show that the latter considerably decorrelates the morphological statistics and makes them more robust because they are less sensitive to the measurements at extreme levels. We compare these results with those from 1000 Gaussian Monte Carlo maps with the same sky coverage, noise properties and power spectrum, and conclude that the \qmask map is neither a very typical nor a very exceptional realization of a Gaussian field. At least about 20% of the 1000 Gaussian Monte Carlo maps differ more than the \qmask map from the mean morphological parameters of the Gaussian fields.