Difference between revisions of "Beams LFI"

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== Main Beams and Focal Plane calibration ==
 
== Main Beams and Focal Plane calibration ==
 
Describe the RIMO content (beam section)
 
Describe the RIMO content (beam section)
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The beam solid angle, Ω<math>_A </math>, of an antenna is given by
 
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: <math> Ω_A \; = \; \int_{4π} \;  P_n(θ,φ) \; dΩ \; = \; \int^{2π}_0 \int^π_0 \; P_n(θ,φ) \; sinθ \; dθ \; dφ </math>
 
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\Omega
 
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where <math>P_n (θ, φ) \; </math> is the normalized power pattern and the field computed by GRASP is normalised to a total power of 4π watt, i.e.,
 
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: <math> \int^{2π}_0 \int^π_0 \; P_n(θ,φ) \; sinθ \;  dθ \; dφ \; = \; 4π </math>
 
  
 
== Effective beams ==
 
== Effective beams ==

Revision as of 14:21, 25 February 2013

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]

Describe the RIMO content (beam section)

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.

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