Beams LFI

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Revision as of 14:51, 25 February 2013 by Fvilla (talk | contribs) (Main Beams and Focal Plane calibration)
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Wish List[edit]

list of information to be inserted in the explanatory supplements

- Description of LFI FOV.

- Description of various telescope models as reported in the beam paper.

- Format of beam data

- Definition of various coordinate frames for beams

Overview[edit]

LFI is observing the sky with 11 pairs of beams associated with the 22 pseudo-correlation radiometers. Each beam of the radiometer pair (Radiometer Chain Assembly - RCA) is named as LFIXXM or LFIXXS. XX is the RCA number ranging from 18 to 28; M and S are the two polarization namely main-arm and side-arm of the Orthomode transduccers #darcangelo2009b.

Figure 1. A sketch of the Planck LFI field of view in the (u,v) plane is shown. The polarization direction on the sky are highlighted by the colored arrows. The M-polarization is shown in green and the S-polarization in red. Main beam shapes are shown for completness and they are not representative of flight beams.



Main Beams and Focal Plane calibration[edit]

As the focal plane calibration we refer to the determination of the beam pointing parameters in the nominal Line of Sight (LOS) frame through main beam measurments using Jupiter transits. the parametes that characterise the beam pointing are the following:

Effective beams[edit]

TBW

Window Functions[edit]

TBW

Sidelobes[edit]

TBW

References[edit]

<biblio force=false>

  1. References

</biblio>

(Planck) Low Frequency Instrument

Field-Of-View

LFI Radiometer Chain Assembly

[LFI meaning]: absolute calibration refers to the 0th order calibration for each channel, 1 single number, while the relative calibration refers to the component of the calibration that varies pointing period by pointing period.

Line Of Sight