Difference between revisions of "Map-making"

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Zodiacal Emission is removed from the 353, 545 and 857 GHz channels. It is described in <span style="color:red">the HFI DPC Paper</span>, but a synopsis of the procedure is as follows:
 
Zodiacal Emission is removed from the 353, 545 and 857 GHz channels. It is described in <span style="color:red">the HFI DPC Paper</span>, but a synopsis of the procedure is as follows:
 
* During each survey, a large fraction of the sky has observations which all fall within a week of each other. That is, during a single survey, most pixels are observed during a short, well-defined period. The contribution from Zodiacal Emission to the total brightness seen, then, is well defined.  
 
* During each survey, a large fraction of the sky has observations which all fall within a week of each other. That is, during a single survey, most pixels are observed during a short, well-defined period. The contribution from Zodiacal Emission to the total brightness seen, then, is well defined.  
* We use the the COBE model of the Zodiacal Light to make predictions for this emission.  
+
* We use the the COBE model of the Zodiacal Light to make predictions for this emission for those pixels observed over a span of one week or less.  
 
* We fit the survey difference maps with these model templates to estimate the emissivity of each component at the Planck wavelengths.  
 
* We fit the survey difference maps with these model templates to estimate the emissivity of each component at the Planck wavelengths.  
 
* We reconstruct the full mission using the combination of the COBE geometric model with the emissivities determined above.  
 
* We reconstruct the full mission using the combination of the COBE geometric model with the emissivities determined above.  

Revision as of 12:02, 18 October 2012

Introduction[edit]

Flux calibration[edit]

Noise properties[edit]

Zodi correction[edit]

Zodiacal Emission is removed from the 353, 545 and 857 GHz channels. It is described in the HFI DPC Paper, but a synopsis of the procedure is as follows:

  • During each survey, a large fraction of the sky has observations which all fall within a week of each other. That is, during a single survey, most pixels are observed during a short, well-defined period. The contribution from Zodiacal Emission to the total brightness seen, then, is well defined.
  • We use the the COBE model of the Zodiacal Light to make predictions for this emission for those pixels observed over a span of one week or less.
  • We fit the survey difference maps with these model templates to estimate the emissivity of each component at the Planck wavelengths.
  • We reconstruct the full mission using the combination of the COBE geometric model with the emissivities determined above.
  • We remove the reconstruction above from each ring of data.
  • We then make maps as described in section ?????

Far Sidelobe Correction[edit]

CO Correction[edit]

Map validation[edit]

[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.

(Planck) High Frequency Instrument

Data Processing Center