Odin observations of H2O in the Galactic Centre
2003 (English)In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 402, L63-L67 p.Article in journal (Refereed) Published
The Odin satellite has been used to detect emission and absorption in the 557-GHz H216O line in the Galactic Centre towards the Sgr Astar Circumnuclear Disk (CND), and the Sgr A +20 km s-1 and +50 km s-1 molecular clouds. Strong broad H2O emission lines have been detected in all three objects. Narrow H2O absorption lines are present at all three positions and originate along the lines of sight in the 3-kpc Spiral Arm, the -30 km s-1 Spiral Arm and the Local Sgr Spiral Arm. Broad H2O absorption lines near -130 km s-1 are also observed, originating in the Expanding Molecular Ring. A new molecular feature (the ``High Positive Velocity Gas'' - HPVG) has been identified in the positive velocity range of ~+120 to +220 km s-1, seen definitely in absorption against the stronger dust continuum emission from the +20 km s-1 and +50 km s-1 clouds and possibly in emission towards the position of Sgr Astar CND. The 548-GHz H218O isotope line towards the CND is not detected at the 0.02 K (rms) level. Based on observations with Odin, a Swedish-led satellite project funded jointly by the Swedish National Space Board (SNSB), the Canadian Space Agency (CSA), the National Technology Agency of Finland (Tekes) and Centre National d'Études Spatiales (CNES). The Swedish Space Corporation was the industrial prime contractor and is also responsible for the satellite operation.
Place, publisher, year, edition, pages
2003. Vol. 402, L63-L67 p.
Galaxy: center, ISM: individual objects: Sgr A, ISM: molecules, ISM: clouds
Research subject Astronomy
IdentifiersURN: urn:nbn:se:su:diva-30919DOI: 10.1051/0004-6361:20030341OAI: oai:DiVA.org:su-30919DiVA: diva2:274761