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, type .r run_pointing
• Several plot windows might be on top of each other
• Follow instructions returned by the code in the terminal. 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, type .r run_pointing_liss
• Several plot windows might be on top of each other
• Follow instructions returned by the code in the terminal

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, type .r run_focus
• Several plot windows might be on top of each other
• Follow instructions returned by the code in the terminal

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 each other
• Follow instructions returned by the code in the terminal

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, type .r run_skydip
• Several plot windows might be on top of each other
• Follow instructions returned by the code in the terminal

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_otf_geometry
• Several plot windows might be on top of each other
• Follow instructions returned by the code in the terminal

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 (On-the-Fly and 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, type .r run_otf_map
• Several plot windows might be on top of each other

Polarization maps

All maps (On-the-Fly and Lissajous) in Polarization Mode 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, type .r run_otf_polar_maps
• Several plot windows might be on top of each other

Data products

Data products for the 1st NIKA pool