Difference between revisions of "Scanning Beams"

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(Note on the file format)
(Note on the file format)
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The stokes map files consist in four columns containing the Stokes parameters for each sample.  
 
The stokes map files consist in four columns containing the Stokes parameters for each sample.  
The columns are called "Beamdata"  , "BeamdataQ", "BeamdataU" and "BeamdataV", containing respectively the <math>I</math>, <math>Q</math>, <math>U</math> and <math>V</math> Stokes parameters.
+
The columns are called "Beamdata"  , "BeamdataQ", "BeamdataU" and "BeamdataV", containing respectively <math>I</math>, <math>Q</math>, <math>U</math> and <math>V</math>.
 
There are differences in the data format between the Main Beam and the near and far Sidelobes.
 
There are differences in the data format between the Main Beam and the near and far Sidelobes.
  

Revision as of 13:32, 17 December 2014

We released maps of the Stokes parameters of the band-averaged scanning beams. The Stokes parameters maps contain the complete information about the field intensity and polarization properties. Main Beam, Intermediate Beam, and Sidelobes are released separately.

Note on the file format

The stokes map files consist in four columns containing the Stokes parameters for each sample. The columns are called "Beamdata" , "BeamdataQ", "BeamdataU" and "BeamdataV", containing respectively [math]I[/math], [math]Q[/math], [math]U[/math] and [math]V[/math]. There are differences in the data format between the Main Beam and the near and far Sidelobes.

Main Beams are projected on the tangent plane to the sphere, and sampled on a grid. The dimension of the grid is given by the keywords "Nx" and "Ny", representing the number of columns and rows. Each of the four stokes columns contain the succession of the [math]Nx \times Ny[/math] samples in major order. The keywords "Xcentre" and "Ycentre" contain the coordinates of the beam maximum (i.e where the sphere intersect the tangent plane).

Sidelobes are sampled on the sphere. The resolution in [math]\theta[/math] and [math]\phi[/math] is given by the keywords "Ntheta" and "Nphi". The columns contain the succession of Nphi Stokes parameters for each [math]\theta[/math].