Issue |
EAS Publications Series
Volume 75-76, 2015
Conditions and Impact of Star Formation
|
|
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Page(s) | 199 - 200 | |
Section | Star Formation: Physical and Chemical Conditions, Feedback | |
DOI | https://doi.org/10.1051/eas/1575038 | |
Published online | 20 May 2016 |
R. Simon, R. Schaaf and J. Stutzki (eds)
EAS Publications Series, 75–76 (2015) 199-200
Surprisingly weak fine-structure line emission from S 140
1 I. Physikalisches Institut der Universität zu Köln, Germany
2 SRON Netherlands Institute for Space Research, Groningen, The Netherlands
3 Kapteyn Astronomical Institute, University of Groningen, The Netherlands
4 Tata Institute of Fundamental Research, Mumbai, India
GREAT observations of the [Oi] and [Cii] fine-structure lines in S 140 show very low intensities towards the embedded sources. We measure line-to-continuum cooling ratios of 10−5 − 10−4, i.e. values matching the far-IR line deficit seen in ULIRGs. Normal PDR models fail to explain the combination of source size, line ratios, and absolute line intensities. A match is, however, possible when modelling the sources in terms of inside-out PDRs. The small beam-filling of PDRs in a dense homogeneous medium can lead to a line deficit compared to the infrared continuum, emitted from a much larger region.
© EAS, EDP Sciences, 2016