Testing the CMB Data for Systematic Effects

Under the assumption that the concordance Lambda cold dark matter (CDM) model is the correct model, we test the cosmic microwave background (CMB) anisotropy data for systematic effects by examining the band pass temperature residuals with respect to this model. Residuals are plotted as a function of l, galactic latitude, frequency, calibration source, instrument type and several other variables that may be associated with potential systematic effects. Linear fitting to the residuals indicates no significant identifiable systematic errors associated with these variables, except for the case of galactic latitude. We find evidence for a trend associated with the absolute galactic latitude range at more than the 2-sigma level. This may be indicative of galactic contamination and may require a 2% reduction in the normalisation of low galactic latitude observations.