Scanning Beams

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We released maps of the Stokes parameters of the band-averaged scanning beams. The Stokes parameters maps contain the complete information on 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 the [math]I[/math], [math]Q[/math], [math]U[/math] and [math]V[/math] Stokes parameters. 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].