Spectra of CO J = 1–0 (bottom) and J = 2–1 (top) at the position C1a for a spectral resolution of 0.5 km s⁻¹. Gaussian fits to lines marginally detected with the highest integrated signal-to-noise emission are shown as a green line. The velocities of the Gaussian peaks are indicated by green vertical dashed lines. The horizontal blue lines at the bottom of each panel indicate the expected velocity range (as given by the C1a Hα line velocity ±20 km s⁻¹).