CMB polarization data plots, almost a vector field, then what?

[Spinnor]

The data points of the polarization of the CMB are a magnitude and an orientation that varies between 0° and 180°. What kind of mathematical field is that, not quite a vector field?

Thanks for any help!

 

[Chalnoth]

The data points of the polarization of the CMB are a magnitude and an orientation that varies between 0° and 180°. What kind of mathematical field is that, not quite a vector field?

Thanks for any help!

This is how polarization on the sky is often defined mathematically:
http://en.wikipedia.org/wiki/Stokes_parameters

 

[bcrowell]

And what are the red and blue colors in the plots?

 

[Spinnor]

And what are the red and blue colors in the plots?

Temperature fluctuations?