A new search for nebulae surrounding Wolf-Rayet stars

The authors have used the plate data from 'An Emission Line Survey of the Milky Way' by Parker, Gull and Kirschner (1979) to make a new search for ring nebulae around Wolf-Rayet stars. The Survey consists of narrow-band interference filter direct imagery centered on the emission lines of Hα + [N II] at lambda6570, [O III] at lambda5007, and [S II] at lambda6730. They have discovered at least five new ring nebulae. Of the fifteen ring nebulae detected on the Survey, including the new discoveries, eleven were brighter in the [O III] bandpass than in the Hα + [N II] bandpass and were filamentary in [O III]. Thirty additional shell-like structures have been identified as ''possible'' or ''probable'' ring nebulae associated with Wolf-Rayet stars. (Auth.)