Skip to main content
We gratefully acknowledge support from the Simons Foundation, member institutions, and all contributors. Donate
arXiv logo
Cornell University Logo

Astrophysics

arXiv:astro-ph/9603115 (astro-ph)
[Submitted on 21 Mar 1996]

Title:Near Infrared Spectroscopy of the Ultracompact HII region G45.12+0.13

Authors:Stuart Lumsden (AAO), Phil Puxley (ROE)
View PDF
Abstract: We present complete, low resolution IJHK spectroscopy of the ultracompact HII region, G45.12+0.13. From the observed HI line strengths, we derive a near infrared extinction law that is slightly steeper than the average. After correction with this extinction law, we find good agreement between the observed line ratios of HeI, Fe+, Fe++, S+ and S++ and the available atomic data. Our data show that the density within the core of G45.12+0.13 must be at least 10^4/cm^3. This is consistent with the known radio structure of the HII region and in considerable disagreement with previous work using mid and far infrared lines. There must also be considerable opacity in the HeI 2 3P-2 3S transition, and we show how the observed strengths of the other HeI lines are consistent with this. From modelling the photoionisation structure, we find good agreement with most of the observed data if the hottest star present has Teff < 42000K. Consideration of the helium ionisation state places a lower limit on this value so that we can also constrain Teff > 38000K. Discrepancies still exist between some of the observed and model line ratios, but the most obvious tend to be the mid-IR observations.
Comments: 17 pages Latex source, 5 postscript figures and macros. gzipped tar file. TO appear in Monthly Notices of the Royal Astronimcal Society. Also available by anonymous ftp from this ftp URL (uuencoded gzipped tar file)
Subjects: Astrophysics (astro-ph)
Report number: AAO PP297-96
Cite as: arXiv:astro-ph/9603115
  (or arXiv:astro-ph/9603115v1 for this version)
  https://doi.org/10.48550/arXiv.astro-ph/9603115
Related DOI: https://doi.org/10.1093/mnras/281.2.493

Submission history

From: Stuart Lumsden [view email]
[v1] Thu, 21 Mar 1996 06:30:00 UTC (101 KB)
Full-text links:

Access Paper:

  • View PDF
  • TeX Source
  • Other Formats
view license
Current browse context:
astro-ph
< prev   |   next >
new | recent | 1996-03

References & Citations

export BibTeX citation

Bookmark

BibSonomy logo Reddit logo

Bibliographic and Citation Tools

Bibliographic Explorer (What is the Explorer?)
Connected Papers (What is Connected Papers?)
Litmaps (What is Litmaps?)
scite Smart Citations (What are Smart Citations?)

Code, Data and Media Associated with this Article

alphaXiv (What is alphaXiv?)
CatalyzeX Code Finder for Papers (What is CatalyzeX?)
DagsHub (What is DagsHub?)
Gotit.pub (What is GotitPub?)
Hugging Face (What is Huggingface?)
Papers with Code (What is Papers with Code?)
ScienceCast (What is ScienceCast?)

Demos

Replicate (What is Replicate?)
Hugging Face Spaces (What is Spaces?)
TXYZ.AI (What is TXYZ.AI?)

Recommenders and Search Tools

Influence Flower (What are Influence Flowers?)
CORE Recommender (What is CORE?)
IArxiv Recommender (What is IArxiv?)

arXivLabs: experimental projects with community collaborators

arXivLabs is a framework that allows collaborators to develop and share new arXiv features directly on our website.

Both individuals and organizations that work with arXivLabs have embraced and accepted our values of openness, community, excellence, and user data privacy. arXiv is committed to these values and only works with partners that adhere to them.

Have an idea for a project that will add value for arXiv's community? Learn more about arXivLabs.

Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)