¹³CO (solid green), CO(2–1) (dashed red), and CO(3–2) (semidashed blue) spectra averaged over the 5σ contour level in the integrated flux maps for each line applied to the spectral cube and centered on Par-Lup3-4. The black line represents the system velocity of Par-Lup3-4, i.e., the velocity average of gas, obtained from ¹³CO, ∼3.7 km s⁻¹. Blueshifted material is lower than 3.45 km s⁻¹ and redshifted material is greater than 3.90 km s⁻¹.