Optical spectra of radio planetary nebulae in the Small Magellanic Cloud

We present preliminary results from spectral observations of four (4) candidate radio sources co-identified with known planetary nebulae (PNe) in the Small Magellanic Cloud (SMC). These were made using the Radcliffe 1.9-meter telescope in Sutherland, South Africa. These radio PNe were originally found in Australia Telescope Compact Array (ATCA) surveys of the SMC at 1.42 and 2.37 GHz, and were further confirmed by new high resolution ATCA images at 6 and 3 cm (4″/2″). Optical PNe and radio candidates are within 2″ and may represent a sub-population of selected radio bright objects. Nebular ionized masses of these objects may be 2.6 M⊙ or greater, supporting the existence of PNe progenitor central stars with masses up to 8 M⊙