Position-velocity diagram taken along the major axis of the circumnuclear disk of PKS B1718–649 (PA = 72°), with a slit of 0.2′′. The dashed horizontal line shows the systemic velocity of the source. The vertical dashed line shows the position of the radio continuum sources. Contour levels are − 5, −3, −2σ, in white, and 3, 6, 12, 18, 24σ, in black. Absorption is detected with ~7σ significance at v ~ 4615 km s⁻¹ and zero offset.