Differences between revisions 13 and 14

NIKA Data Reduction

Contents

NIKA Data Reduction

Getting ready

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

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

Shortly after a scan is done, the NIKA scientific data, the xml information generated by PAKO (and the AntennaIMBfits shortly after) 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

All calibration scans are reduced by the same routine: IDL> rta_reduce, day, scan_num

Informations or actions to be taken by the observer appear on the plots and explicitely in IDL terminal window:

cont_pointing_cross

The plots show 1D profiles of the azimuth or elevation scans and a gaussian fit of the source. The displayed offsets refer to the reference detectors and are not meant to be passed to PAKO.
The maps show the source, a cross at the location of the reference pixel and gaussian fit of the source
In the terminal window, the observer should follow the instruction (e.g.): B 2mm (MAP) (for PAKO) SET POINTING 3.0 0.7
the pointing reference is the 2mm channel.
If the sky conditions were correct, instructions at 1 and 2mm should be in good agreement.
if a glitch corrupts the maps but the 1d profiles are ok, the user can follow the instruction B 2mm, : (TOI) (for PAKO) SET POINTING 3.0 0.7
In good conditions, all instructions agree to better than 1 arcsec.

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

Neel pipeline

The following diagram shows the NIKA data flow from the IRAM 30m telescope to the observers' accounts.

alt text

-  ⇤ ← Revision 13 as of 2014-02-17 14:27:48 → 
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  Editor: NikaBolometer
  Comment:
+   ← Revision 14 as of 2014-02-17 14:28:18 → ⇥
  Size: 4879
  Editor: NikaBolometer
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
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-* In the terminal window, the observer should follow the instruction (e.g.): B 2mm (MAP) (for PAKO) SET POINTING 3.0 0.7
* the pointing reference is the 2mm channel.
* If the sky conditions were correct, instructions at 1 and 2mm should be in good agreement.
* if a glitch corrupts the maps but the 1d profiles are ok, the user can follow the instruction B 2mm, : (TOI) (for PAKO) SET POINTING 3.0 0.7
* In good conditions, all instructions agree to better than 1 arcsec.
+ * In the terminal window, the observer should follow the instruction (e.g.): B 2mm (MAP) (for PAKO) SET POINTING 3.0 0.7
 * the pointing reference is the 2mm channel.
 * If the sky conditions were correct, instructions at 1 and 2mm should be in good agreement.
 * if a glitch corrupts the maps but the 1d profiles are ok, the user can follow the instruction B 2mm, : (TOI) (for PAKO) SET POINTING 3.0 0.7
 * In good conditions, all instructions agree to better than 1 arcsec.

Diff for "Continuum/NIKA/DataReduction"