Outflows in ULIGs

High-velocity outflow components have been detected for HI and several molecules lines in prominent FIR galaxies. A correlation has been made between the nuclear activity that results in FIR-prominence and the outflow velocity as indicated by the blue edge of the lines. The observed HI absorption, OH absorption and emission, formaldehyde absorption, and water-vapor emission occurs in edge-on molecular disks that are perturbed by the (circum-)nuclear starburst or super-star-clusters. The observed outflows may serve as a diagnostic probe for the state of the high-density molecular gas components.