Wilkinson Microwave Anisotropy Probe has provided cosmic microwave background (CMB) maps of the full sky. The raw data are subject toforeground contamination, in particular near to the Galactic plane. Foreground-cleaned maps have been derived, e.g. the internal linearcombination map of Bennett et al., and the reduced foreground TOH map ofTegmark et al. Using S statistics, we examine whether residual foreground contamination is left over in the foreground-cleaned maps. Inparticular, we specify which parts of the foreground-cleaned maps are sufficiently accurate for the circle-in-the-sky signature. We generalizethe S statistic, called D statistic, such that the circle test can dealwith CMB maps in which the contaminated regions of the sky are excludedwith masks.
- methods: data analysis
- methods: statistical
- cosmic microwave background
- cosmology: miscellaneous
- large-scale structure of Universe