NIKA Data Reduction

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Getting ready

To start the IDL session for the real time analysis, open a terminal and type: analaysis.

   $ ssh -X nikaw-13@mrt-lx1
   $ ssh_sami
   > rt
   > emacs &
   > idl 

Shortly after a scan is done, the NIKA scientific data and the AntennaIMBfits are written on SAMI and can be processed. There are two types of observation: the “science” scans and the “calibration” scans. There is a specific routine to analyze each type of scan.

Calibration scans

The calibration scans expect actions from the observer and interaction with PaKo.

cont_pointing_cross

• In the emacs window, edit run pointing.pro and update the day and scan num parameters.
• update the p2cor and p7cor parameters with the “SET POINTING” values displayed in the PAKO window.
• Save the file
• In the idl session in T2, type .r run pointing
• Several plot windows might be on top of eachother
• Follow instructions returned by the code in T2. By default, follow instructions “B (2mm) : (MAP) (for PAKO and pointing model)”.

cont_pointing_liss

• In the emacs window, edit run pointing liss.pro and update the day and scan num parameters.
• Save the file
• In the idl session in T2, type .r run pointing liss
• Several plot windows might be on top of eachother
• Follow instructions returned by the code in T2

cont_focus_track

• In the emacs window, edit run focus.pro and update the day and scan num parameters.
• Check the value of focusz in the PAKO display window.
• Do not change the fooffset values unless you have modified the pako script focusp.pako.
• Save the file
• In the idl session in T2, type .r run focus
• Several plot windows might be on top of eachother
• Follow instructions returned by the code in T2

cont_focus_liss

• In the emacs window, edit run focus liss.pro and update the day and scan num parameters. Scan num should be the first of the five scans involved in this analysis.
• Save the file
• In the idl session in T2, type .r run focus liss
• Several plot windows might be on top of eachother
• Follow instructions returned by the code in T2

cont_skydip

• In the emacs window, edit run skydip.pro and update the day and scan num parameters.
• Save the file
• In the idl session in T2, type .r run skydip
• Several plot windows might be on top of eachother
• Follow instructions returned by the code in T2

cont_beammap

• In the emacs window, edit run otf geometry.pro and update the day and scan num parameters.
• Save the file
• In the idl session in T2, type .r run otg geometry
• Several plot windows might be on top of eachother
• Follow instructions returned by the code in T2

Science scans

The science scans are meant to be optimally processed offline with tailored procedures. The real time software mentioned in this note only aims at giving a quick feedback

Total power maps

All maps (cont_onthefly and cont_lissajous) in total power mode can be reduced by the same script:

• In the emacs window, edit run otf map.pro and update the scan num and day parameters.
• If you’re observing a point source, set diffuse = 0. If you’re observing diffuse emission set diffuse = 1.
• Save the file
• In the idl session in T2, type .r run otf map
• Several plot windows might be on top of each other

Polarization maps

All maps (OTF or Lissajou) in Polarization modes can be reduced by the same script:

• In the emacs window, edit run otf polar maps.pro and update the scan num and day parameters.
• Save the file
• In the idl session in T2, type .r run otf polar maps
• Several plot windows might be on top of each other

Author: Israel Hermelo (IRAM 30m continuum pool manager)

email: hermelo@iram.es

Created: 2014.02.06

Last update: 2014.02.06