Schematic representation of the way spatial offset and the reconstruction of the polarization plane might be related. The red and purple curves represent two tracks originating from events having the same true impact point, P_i, and being wrongly reconstructed at the track end in the same point, P_r; also, ϕ_i is the polarization plane that would have been reconstructed as tangent to both tracks if the impacts points would have been correctly identified and ϕ_r1 and ϕ_r2 are the polarization planes reconstructed as tangent of the tracks in the point, P_r.