Velocity channel maps of the SiO 5–4 transition emission, integrated over the velocity width of about 4.7 km s⁻¹. The center velocities relative to the systemic velocity of 107.6 km s⁻¹ are listed in the upper right corner of each panel. The intensity scale is shown as a bar above panel (a). The gray contour is the outline of the ¹³CS 5–4 emission in Figure 1. The blue box in panel (l) is the area shown in Figure 6.