Temperature-to-polarization leakage
= Temperature-to-polarization leakage
Instrumental conversion of a larger temperature-intensity signal into apparent sky polarization, for example through unequal channel gains or mismatched beam responses. Relative <calibration>, beam characterization, scan-angle coverage and map-level null tests are needed to control it. Multifrequency foreground removal alone does not establish that instrumental leakage is negligible.