IUE observations of high velocity gas towards the M 16 nebula.

Abstract

The star HD 168183, which is part of the giant H II region-molecular cloud complex of M16 (NGC 6611), has been observed at high resolution using the IUE satellite. High velocity interstellar absorption components have been detected at velocities of -83, -38 and +40 km s^-1 and it is proposed that a stellar wind-driven shock-front, interacting with the ambient neutral interstellar gas, is responsible for such complex velocity structure. Strong absorption from five of the ¹²C¹⁶O UV molecular lines has also been detected and the present UV absorption line data seem consistent with radio observations of M16 in which the Tenorio-Tagle 'champagne' model has been invoked to explain the ionized and neutral gas outflows from the nebula.