Open AccessTesting the Gaussianity of the COBE DMR data with spherical wavelets
Author(s) -
Barreiro R. B.,
Hobson M. P.,
Lasenby A. N.,
Banday A. J.,
Górski K. M.,
Hinshaw G.
Publication year - 2000
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2000.03772.x
Subject(s) - physics , kurtosis , wavelet , skewness , non gaussianity , gaussian , scale (ratio) , sensitivity (control systems) , astrophysics , statistical physics , statistics , artificial intelligence , optics , mathematics , quantum mechanics , cosmic microwave background , electronic engineering , computer science , engineering , anisotropy
We investigate the Gaussianity of the 4‐yr COBE DMR data (in HEALPix pixelization) using an analysis based on spherical Haar wavelets. We use all the pixels lying outside the Galactic cut and compute the skewness, kurtosis and scale–scale correlation spectra for the wavelet coefficients at each scale. We also take into account the sensitivity of the method to the orientation of the input signal. We find a detection of non‐Gaussianity at >99 per cent level in just one of our statistics. Taking into account the total number of statistics computed, we estimate that the probability of obtaining such a detection by chance for an underlying Gaussian field is 0.69. Therefore, we conclude that the spherical wavelet technique shows no strong evidence of non‐Gaussianity in the COBE DMR data.