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Radio Recombination Line Emission from Ultracompact HII Regions

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Book cover Radio Recombination Lines: 25 Years of Investigation

Part of the book series: Astrophysics and Space Science Library ((ASSL,volume 163))

Abstract

We report observations of H30α, H42α, and H76α line emission toward a selection of 12 ultracompact (UC) HII regions. These same UC HII regions have also been imaged with the VLA. Continuum and radio recombination line (RRL) models have been calculated and compared. For the highest density nebulae, single component models do not seem to be consistent with both the continuum and RRL observations. Possisble correlations of line velocities and line widths are considered. Evidence for electron impact broadening is shown.

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References

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Author information

Authors and Affiliations

  1. Astronomy Dept., 475 N. Charter St., Madison, WI, 53706, USA

    E. Churchwell

  2. Max-Planck-Inst., Auf dem Hügel 69, 5300, Bonn 1, West Germany

    C. M. Walmsley

  3. Center for Astrophysics, 60 Garden St., Cambridge, MA, 02138, USA

    D. O. S. Wood

  4. IRAM, Avenida Divina, Pastora 7, 18012, Granada, Spain

    H. Steppe

Authors
  1. E. Churchwell
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  2. C. M. Walmsley
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  3. D. O. S. Wood
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  4. H. Steppe
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Editor information

Editors and Affiliations

  1. National Radio Astronomy Observatory, Tucson, Arizona, USA

    M. A. Gordon

  2. P. N. Lebedev Physical Institute, U.S.S.R. Academic of Sciences, Moscow, USSR

    R. L. Sorochenko

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© 1990 Kluwer Academic Publishers

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Churchwell, E., Walmsley, C.M., Wood, D.O.S., Steppe, H. (1990). Radio Recombination Line Emission from Ultracompact HII Regions. In: Gordon, M.A., Sorochenko, R.L. (eds) Radio Recombination Lines: 25 Years of Investigation. Astrophysics and Space Science Library, vol 163. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-0625-9_7

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  • DOI: https://doi.org/10.1007/978-94-009-0625-9_7

  • Publisher Name: Springer, Dordrecht

  • Print ISBN: 978-94-010-6768-3

  • Online ISBN: 978-94-009-0625-9

  • eBook Packages: Springer Book Archive

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