TOI processing

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Overview[edit]

We describe here the how the TOIs are processed in order to be used for map production. We do not repeat the general features of the pipeline which are given in the HFI Data Processing article (REF). Here we give complementary explanations on some details. The TOI of each bolometer is processed independently of the other bolometers, so as to keep the noise properties as uncorrelated as possible. The processing involves modifying the TOI itself for what concerns the conversion to absorbed power and the correction of glitch tails. It also adds a flag TOI that masks the TOI samples that are not to be projected on maps for various reasons.


Input TOI[edit]

The input TOI consists in the AC modulated voltage output of the readout of each bolometer. The input has previously been decompressed, and converted from internal digital units to voltage via a constant factor. The TOI has a regular sampling at the acquisition frequency of facq=180.373700+-0.000050 Hz. There are almost no missing data in the TOIs, except for few hundred samples of 545 and 857GHz TOIs which are lost in the on-board compression due to saturation on the Galactic Center crossings.

General Pipeline Structure[edit]

A nice detailed figure

Output TOIs and products[edit]

A TOI of clean calibrated samples (ccTOI) and a combined flag TOI (fTOI) are the outputs of the processing. The ccTOI is calibrated so as to represent the instantaneous power absorbed by the detector. It is worth mentioning how the ccTOI is changed with respect to the input TOI, beyond the harmless constant conversion factor from voltage to absorbed power.

Trends in the output processing variables[edit]

(Planck) High Frequency Instrument