THE PLANETARY-NEBULA SURROUNDING THE WC-11 STAR IRAS-17514-1555

Imaging and long-slit spectroscopy of the nebula surrounding the WC11 star IRAS 17514-1555 are presented that allow, for the first time, the nebula to be studied without contamination from the underlying star. These data show that the nebula is photoionized and does not appear to have an obvious scattering component. The nebula consists of two shel ls: a low-density outer region (diameter 18 arcsec) where n(e) approxi mately 50 cm-3 and an unresolved inner nebula (diameter < 1.5 arcsec) where n(e) > 2 x 10(4) cm-3 . The N, O and S abundances derived for th e outer nebula seem typical of PNe but it is likely that He is enhance d. Simple modelling suggests that the nebula is kept in thermal equili brium by a 20000-22000K central star.