Left panel: ¹²CO(1–0) position-velocity diagram along the major axis (PA = 178°) of NGC 3627 using the velocity range from –220 to 220 km s^-1 contoured over a grey-scale representation. Contour levels are from 3σ to 48σ in steps of 3σ (σ = 3.6 mJy beam^-1). The velocities are relative to V_sys,hel (= 744 km s^-1) and X are the offsets along the major axis in arcsecs. Right panel: the same for ¹²CO(2–1). Contour levels are from 3σ to 30σ in steps of 3σ (σ = 6.7 mJy beam^-1).