Nobeyama moment-0 maps for ¹²CO, ¹³CO, and C¹⁸O with the resolution of 21.7″. The white vectors represent the orientation of Planck magnetic fields. Only segments with sufficient signal-to-noise ratio (PI/σ_PI > 3) are plotted. The blue circle in the bottom left marks the resolution of Planck magnetic fields. The black rectangles represent the specific regions with high-resolution polarization observations.