• DOI:10.1093/mnras/sty1929
• Corpus ID: 43391750

The coordinated radio and infrared survey for high-mass star formation – IV. A new radio-selected sample of compact galactic planetary nebulae

@article{Irabor2018TheCR,
  title={The coordinated radio and infrared survey for high-mass star formation – IV. A new radio-selected sample of compact galactic planetary nebulae},
  author={T. Irabor and Melvin Hoare and Ren{\'e} D. Oudmaijer and James S. Urquhart and Stanley Kurtz and S. L. Lumsden and Cormac R. Purcell and Albert A. Zijlstra and G. Umana},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2018}
}

• T. Irabor, M. Hoare, +6 authors G. Umana
• Published 25 March 2018
• Physics
• Monthly Notices of the Royal Astronomical Society

A catalogue of 239 ultra-compact H II  regions (UCHIIs) found in the CORNISH survey at 5 GHz and 1.5″ resolution in the region 10° < l < 65°,  |b| < 1° is presented. This is the largest complete and well-selected sample of UCHIIs to date and provides the opportunity to explore the global and individual properties of this key state in massive star formation at multiple wavelengths. The nature of the candidates was validated, based on observational properties and calculated spectral indices, and the analysis is presented in this work. The physical sizes, luminosities and other physical properties were computed by utilising literature distances or calculating the distances whenever a value was not available. The near- and mid-infrared extended source fluxes were measured and the extinctions towards the UCHIIs were computed. The new results were combined with available data at longer wavelengths and the spectral energy distributions (SEDs) were reconstructed for 177 UCHIIs. The bolometric luminosities obtained from SED fitting are presented. By comparing the radio flux densities to previous observational epochs, we find about 5% of the sources appear to be time variable. This first high-resolution area survey of the Galactic plane shows that the total number of UCHIIs in the Galaxy is ~750 – a factor of 3–4 fewer than found in previous large area radio surveys. It will form the basis for future tests of models of massive star formation.