OPTICAL OBSERVATIONS OF SOUTHERN PLANETARY-NEBULA CANDIDATES

We present H alpha+[NII] images and low resolution spectra of 16 IRAS- selected, southern planetary nebula candidates previously detected in the radio continuum. The H alpha+[NII] images are presented as finding charts. Contour plots are shown for the resolved planetary nebulae. F rom these images mean optical angular diameters were determined. Optic al spectra show that these IRAS-selected and radio detected planetary nebula candidates are indeed planetary nebulae. The values for their e xtinction coefficient is generally very high. More than half of the pl anetary nebulae seem to be of low excitation, having central stars wit h an effective temperature of probably similar to 60 000 K or less.