A pilot study of the radio-continuum emission from MASH planetary nebulae

Abstract

We report an Australia Telescope Compact Array (ATCA) radio-continuum observations of 26 planetary nebulae (PNe) at wavelengths of 3 and 6 cm. This sample of 26 PNe were taken from the Macquarie/AAO/Strasbourg Halpha PNe (MASH) catalogue and previous lists. We investigate radio detection quality including measured and derived parameters for all detected or marginally detected PNe from this combined sample. Some 11 objects from the observed sample have been successfully detected and parametrized. Except for one, all detected PNe have very low radio surface brightnesses. We use a statistical distance scale method to calculate distances and ionised masses of the detected objects. Nebulae from this sample are found to be large (>0.2 pc in diameter) and highly diluted which indicates old age. For 21 PNe from this sample we list integrated Halpha fluxes and interstellar extinction coefficients, either taken from the literature or derived here from the Balmer decrement and radio to Halpha ratio methods. Finally, our detected fraction of the MASH pilot sample is relatively low compared to the non-MASH sub-sample. We conclude that future radio surveys of the MASH sample must involve deeper observations with better uv coverage in order to increase the fraction of detected objects and improve the quality of the derived parameters.

9 pages, 2 figures, and 5 tables. Accepted for publication in Astron. Nachr

References in corpus (5)

• MASH-II: More Planetary Nebulae from the AAO/UKST HαSurvey
• The Magellanic Cloud Calibration of the Galactic Planetary Nebula Distance Scale
• Chemical abundances for Hf 2-2, a planetary nebula with the strongest known heavy element recombination lines
• Radio-continuum detections of Galactic Planetary Nebulae I. MASH PNe detected in large-scale radio surveys
• Optical recombination lines as probes of conditions in planetary nebulae

Cited by in corpus (7)

• The Hα surface brightness - radius relation: a robust statistical distance indicator for planetary nebulae
• A catalogue of integrated H-alpha fluxes for 1,258 Galactic planetary nebulae
• The planetary nebula Abell 48 and its [WN] nucleus
• Flux calibration of the AAO/UKST SuperCOSMOS H-alpha Survey
• High-resolution Very Large Array observations of 18 MIPSGAL bubbles
• DT Serpentis: neither a symbiotic star nor a planetary nebula associate
• MeerKAT discovery of 164 compact radio rings toward the Galactic Plane