Astron. Astrophys. 364, L31-L35 (2000)

Letter to the Editor

Revealing deuterium Balmer lines in H II regions with VLT-UVES ^*

G. Hébrard ¹, D. Péquignot ², J.R. Walsh ³, A. Vidal-Madjar ¹ and R. Ferlet <sup>1

1</sup> Institut d'Astrophysique de Paris, CNRS, 98 bis Boulevard Arago, 75014 Paris, France (hebrard@iap.fr, vidalmadjar, ferlet)
² Laboratoire d'Astrophysique Extragalactique et de Cosmologie associé au CNRS (UMR 8631) et à l'Université Paris 7, DAEC, Observatoire de Paris-Meudon, 92195 Meudon Cédex, France (daniel.pequignot@obspm.fr)
³ Space Telescope European Co-ordinating Facility, European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching bei München, Germany (jwalsh@eso.org)

Received 15 August 2000 / Accepted 25 August 2000

Abstract

The search for deuterium Balmer lines with VLT-UVES is reported in HII regions of the Galaxy and the Magellanic Clouds. The DI lines appear as faint, narrow emission features in the blue wings of the HI Balmer lines and can be distinguished from high-velocity HI emission. The previous identification to deuterium is re-inforced beyond doubt.

The detection of D and D in Orion (Hébrard et al. 2000) is confirmed and deuterium lines are now detected up to at least D. The UVES observations provide the first detection of Balmer DI lines in four new HII regions (M 8, M 16, M 20, and DEM S 103 in SMC), demonstrating that these lines are of common occurence.

Key words: line: identification ISM: atoms, ions ISM: H ii regions ISM: individual objects: M42, M8, M16, M20, M17, DEM S 103

* Based on observations collected at the European Southern Observatory, Paranal, Chile [ESO VLT-UT2 N^o 65.I-0498(A)].

Send offprint requests to: Guillaume Hébrard

SIMBAD Objects

Contents

• 1. Introduction
• 2. Observations
• 3. Results
  • 3.1. Orion Nebula (M 42)
  • 3.2. Lagoon Nebula (M 8)
  • 3.3. Eagle Nebula (M 16)
  • 3.4. Trifid Nebula (M 20)
  • 3.5. DEM S 103 in the Small Magellanic Cloud
  • 3.6. Omega Nebula (M 17): high-velocity structure emission
• 4. Confirming the identification of deuterium
• 5. Conclusion
• Acknowledgements
• References

© European Southern Observatory (ESO) 2000

Online publication: December 15, 2000
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