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Astrophysics and Space Science

, Volume 26, Issue 1, pp 115–122 | Cite as

On the nature of some non radio emitting Sharpless Hii regions

  • M. Felli
  • M. Perinotto
Article

Abstract

Thirty four objects appearing in the SharplessCatalogue of HiiRegions with radio flux densities below 0.1 fu* at 1400 MHz, are studied. It is shown that two of them are planetary nebulae, two are reflection nebulae and two weak emission-reflection nebulae. From statistical arguments it is concluded that six may be evolved planetaries while the remaining are faint nearby Hii regions excited by stars of relatively advanced spectral type.

Keywords

Reflection Flux Density Spectral Type Planetary Nebula Radio Flux 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© D. Reidel Publishing Company 1974

Authors and Affiliations

  • M. Felli
    • 1
  • M. Perinotto
    • 1
  1. 1.Astrophysical Observatory of ArcetriFlorenceItaly

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