Distribution of the angle between polarization and tangential direction. The thin orange lines show the profile corresponding to each LOS; the solid red line is the median profile, and the two dashed red lines denote the first and third quartiles. The red area shows the 3σ confidence limits inferred from our bootstrap experiment (see Appendix B), and the teal line is the distribution taken from H11. We show the profile we obtain by assuming some noise in the angle measurement in black.