Optical Spectra of Radio Planetary Nebulae in the Small Magellanic Cloud

TL;DR

This study reports preliminary spectral observations of radio-identified planetary nebulae in the Small Magellanic Cloud, suggesting they contain relatively massive progenitor stars and are part of a radio-bright subpopulation.

Contribution

It provides new spectral data confirming radio PNe in the SMC and links their properties to progenitor star masses up to 8 solar masses.

Findings

Radio PNe in SMC confirmed with spectral observations

Nebular ionized masses suggest massive progenitor stars

Radio bright PNe may form a distinct subpopulation

Abstract

We present preliminary results from spectral observations of four 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 subpopulation of selected radio bright objects. Nebular ionized masses of these objects may be 2.6 MSol or greater, supporting the existence of PNe progenitor central stars with masses up to 8 MSol.