Top panel: CO SLEDs for the spectral components that lie within the blue rectangle in Fig. 6 probing dynamically quiescent gas. Bottom panel: CO SLEDs for the spectral components that lie outside the blue rectangle in Fig. 6, likely containing molecular outflows in these sources. Only higher-excitation ULIRGs are included in this analysis (see Sect. 3.2). Quiescent components show significantly less excited CO SLEDs compared to the high-v/high-σ spectral components. The dotted gray lines show the thermalized optically thick limit (in all lines) SLED profiles, normalized to the CO(2−1) transition.