HFI performance summary
The essential characteristics of the HFI are gathered in the table below. The HFI has been operating flawlessly for 30 months, the most optimistic duration of the helium reserve of the dilution cooler. The telescope pointing was achieved with an accuracy better than expected and reconstructed to a few seconds of arc. All of the fifty-two bolometers -but two- collected data in very stable conditions during the whole mission, and practically all of the data was correctly recorded.
The extreme sensitivity provided by the 100 mK bolometers and the HFI architecture has provided a view of the submillimetre sky with a noise not far from the fundamental limits set by the photon noise of the observed source. Systematic effects are now measurable. The most noticeable of them are the spikes in the signal produced by cosmic rays hitting the bolometers and their immediate surrounding. In the same time, the overall sensitivity is finally around that announced as the goal in the "bluebook" #planck2005-bluebook, i.e. twice better than the required sensitivity. One can expect to improve these numbers by about root two when the whole mission data is available.
|Frequency||100 GHz||143 GHz||217 GHz||353 GHz||545 GHz||857 GHz|
|Beam size (FWHM, arcmin)||9.66||7.27||5.01||4.86||4.84||4.63|
|Sensitivity per fiducial pixel||3.95 µK/K||2.35 µK/K||4.58 µK/K||15.17 µK/K||0.013 Mjy/sr||0.013 Mjy/sr|
(Planck) High Frequency Instrument