CO 3–2 PV diagram along the arrow labeled D3 shown as a green dashed arrow in Fig. 1a. The position axis originates from the start of the arrow in Fig. 1a. The intensity is smoothed over 5 channels. The contours are − 12σ, − 6σ, − 3σ, 3σ, 6σ, 12σ, 24σ, and 48σ with σ = 2.0 mJy beam⁻¹. The red and blue dashed lines show the inner integration limits while the black dashed line indicates the systemic velocity of Cha-MMS1.