Asymmetries in the local curvature of the WMAP data

Abstract

We use the local curvature to investigate the possible existence of non-Gaussianity/asymmetry in the WMAP data. Considering the full sky we find results which are consistent with the Gaussian assumption. However, strong non-Gaussian features emerge when considering the northern and southern galactic hemisphere separately, particularly on scales between 1 and 5 degrees. Quite interestingly, the maximum non-Gaussianity is found for hemispheres centered near the ecliptic poles, which might suggest the presence of some systematic effect. The direction of the asymmetry seems consistent with the findings by Eriksen et al. 2004.

Submitted to ApJ Letters

References in corpus (5)

• Asymmetries in the CMB anisotropy field
• Detection of non-Gaussianity in the WMAP 1-year data using spherical wavelets
• Non-Gaussian Signatures in the Temperature Fluctuation Observed by the Wilkinson Microwave Anisotropy Probe
• Phase cross-correlation of the WMAP ILC map and foregrounds
• 3-point temperature anisotropies in WMAP: Limits on CMB non-Gaussianities and non-linearities

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