Skip to content
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Menu
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Menu
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Publication Details
AFRICAN RESEARCH NEXUS
SHINING A SPOTLIGHT ON AFRICAN RESEARCH
earth and planetary sciences
Herschel measurements of molecular oxygen in Orion
Astrophysical Journal, Volume 737, No. 2, Article 96, Year 2011
Notification
URL copied to clipboard!
Description
We report observations of three rotational transitions of molecular oxygen (O2) in emission from the H2 Peak 1 position of vibrationally excited molecular hydrogen in Orion. We observed the 487 GHz, 774 GHz, and 1121 GHz lines using the Heterodyne Instrument for the Far Infrared on the Herschel Space Observatory, having velocities of 11kms-1 to 12kms-1 and widths of 3kms-1. The beam-averaged column density is N(O2) = 6.5 × 1016cm-2, and assuming that the source has an equal beam-filling factor for all transitions (beam widths 44, 28, and 19″), the relative line intensities imply a kinetic temperature between 65K and 120K. The fractional abundance of O 2 relative to H2 is (0.3-7.3) × 10-6. The unusual velocity suggests an association with a 5″ diameter source, denoted Peak A, the Western Clump, or MF4. The mass of this source is ∼10 M ⊙ and the dust temperature is ≥150K. Our preferred explanation of the enhanced O2 abundance is that dust grains in this region are sufficiently warm (T ≥ 100 K) to desorb water ice and thus keep a significant fraction of elemental oxygen in the gas phase, with a significant fraction as O2. For this small source, the line ratios require a temperature ≥180K. The inferred O2 column density ≃5 × 1018cm-2 can be produced in Peak A, having N(H 2) ≃ 4 × 1024cm-2. An alternative mechanism is a low-velocity (10-15kms-1) C-shock, which can produce N(O2) up to 1017cm-2. © 2011. The American Astronomical Society. All rights reserved.
Authors & Co-Authors
Goldsmith, Paul F.
United States, Pasadena
California Institute of Technology
Black, John H.
Sweden, Gothenburg
Chalmers University of Technology
Li, D. H.
United States, Pasadena
California Institute of Technology
Pagani, Laurent
France, Neuville-sur-oise
Lerma - Laboratoire D'études du Rayonnement et de la Matière en Astrophysique et Atmosphères
Benz, Arnold O.
Switzerland, Zurich
Eth Zürich
Bergin, Edwin Anthony
United States, Ann Arbor
University of Michigan, Ann Arbor
Caselli, Paola
United Kingdom, Leeds
University of Leeds
Caux, Emmanuel
France, Toulouse
Observatoire Midi-pyrénées
France, Paris
Cnrs Centre National de la Recherche Scientifique
Encrenaz, Pierre J.
France, Neuville-sur-oise
Lerma - Laboratoire D'études du Rayonnement et de la Matière en Astrophysique et Atmosphères
Falgarone, Edith G.
France, Paris
L'observatoire de Paris
Gérin, Maryvonne
France, Paris
L'observatoire de Paris
Nagy, Zsófia
Netherlands, Utrecht
Sron Netherlands Institute for Space Research
Roueff, Evelyne M.
France, Paris
L'observatoire de Paris
Sandqvist, Aage A.
Sweden, Stockholm
Albanova Universitetscentrum
van der Tak, Floris F.S.
Netherlands, Utrecht
Sron Netherlands Institute for Space Research
van Dishoeck, Ewine F.
Netherlands, Leiden
Universiteit Leiden
Germany, Garching Bei Munchen
Max Planck Institute for Extraterrestrial Physics
Vastel, Charlotte
France, Toulouse
Observatoire Midi-pyrénées
France, Paris
Cnrs Centre National de la Recherche Scientifique
Viti, Serena
United Kingdom, London
University College London
Statistics
Citations: 114
Authors: 18
Affiliations: 20
Identifiers
Doi:
10.1088/0004-637X/737/2/96
ISSN:
0004637X
Research Areas
Environmental