OH and H I absorption at the nucleus of NGC 660

Abstract

High-resolution interferometric data of the H I and OH absorption in the nuclear region of NGC 660 reveal three distinct absorbing structures. The central disk of the galaxy with a large velocity gradient dominates the absorption signature. The gas in the warped outer disk appears in absorption close to the systemic velocity; the outer rings of the warp located at large radii are moving in front of the nuclear radio source. Third, an outflowing feature can be seen at the center of the radio source at 100 km s −1 below the systemic velocity. This mostly molecular feature could be due to a perturbed spiral structure in the inner regions of the disk