Variation in the degree of polarization (top panel) and polarization angle (bottom panel) with r_p𝑔eo for all the stars (members and nonmembers) observed in the direction of the anticenter. The black points with error bars represent the average P and θ values in r_p𝑔eo distance bins of 500 pc width. The error bars correspond to the standard deviation in the P and θ values in each distance bin. The distance to the spiral arms is marked by vertical lines using the same colors as in Fig. 7.