Polarized emission distribution from HD 163296 in H and K_S bands. Top: radial profile obtained from a 3 pixel-wide cut along the major axis (left side is East). Bottom: azimuthal profile obtained by integrating over concentric ellipses from 0.6″ to 0.7″ (see text for details). Only detections with more than 3σ are shown. The errors and the sensitivity are calculated from the local noise in both the Q_T and U_T images. The sensitivity bumps are due to the AO spots. Systematic errors from the photometric calibration are not included. The vertical grey stripes in the azimuthal profile indicate the location of the major axis.