Azimuthally averaged continuum emission profile (gray, normalized to unity at B98) and intensity profile of C₂H 3−2 (blue, normalized to unity at the peak). The normalized pebble surface densities and C₂H column densities at t = 176 orbits in the default run are shown in orange and green for comparison; they are respectively convolved by 0.1 arcsec and 0.15 arcsec beams used in the MAPS observation. The dashed and solid vertical lines coincide with the D76 gap and the B98 ring in the continuum, respectively.