NPIPE reprocessing

NPIPE reprocessing is a full-frequency or detector-set-wide processing step. It covers the entire span of the Planck mission. During reprocessing, NPIPE corrects systematics in the time-ordered data by fitting time-domain systematics templates. The templates being fitted are:

• gain fluctuations;
• bandpass mismatch;
• ADC nonlinearity;
• bolometric transfer-function residuals;
• zodiacal light;
• far sidelobe signal.

In addition, NPIPE breaks certain large-scale degeneracies in the fitting by making an approximation that the sky polarization at 44-143GHz can be modelled as a linear combination of the 30-, 217-, and 353-GHz polarization maps. These polarization templates are unrolled into the time domain in the reprocessing step.

Below is the schematic of the reprocessing sub pipeline. The diagram is reproduced from A&A 643, A42 (2020).