Book contents
- Frontmatter
- Contents
- Preface
- Conference participants
- Conference photograph / poster
- 1 Physics of H2 and HD
- 2 Formation - Destruction
- 3 Observations and Models
- Non Stationary C-shocks: H2 Emission in Molecular Outflows
- The Ortho/Para Ratio in C and J-type Shocks
- Theoretical Models of Photodissociation Fronts
- ISO Spectroscopy of H2 in Star Forming Regions
- Observations of the H2 Ortho-Para Ratio in Photodissociation Regions
- H2 Emission from CRL618
- Hydrogen in Photodissociation Regions: NGC2023 and NGC7023
- A Pre-FUSE View of H2
- H2 Absorption Line Measurements with ORFEUS
- Ultraviolet Observations of Molecular Hydrogen in Interstellar Space
- FUSE and Deuterated Molecular Hydrogen
- ISO-SWS Observations of H2 in Galactic Sources
- H2 in Molecular Supernova Remnants
- 3D Integral Field H2 Spectroscopy in Outflows
- Near-Infrared Imaging and [OI] Spectroscopy of IC443 using 2MASS and ISO
- ISOCAM Spectro-imaging of the Supernova Remnant IC443
- Spatial Structure of a Photo-Dissociation Region in Ophiucus
- Tracing H2 Via Infrared Dust Extinction
- The Small Scale Structure of H2 Clouds
- Hot Chemistry in the Cold Diffuse Medium: Spectral Signature in the H2 Rotational Lines
- H2 Observations of the OMC-1 Outflow with the ISO-SWS
- 4 Extragalactic and Cosmology
- 5 Outlook
- Author index
H2 Observations of the OMC-1 Outflow with the ISO-SWS
from 3 - Observations and Models
Published online by Cambridge University Press: 04 August 2010
- Frontmatter
- Contents
- Preface
- Conference participants
- Conference photograph / poster
- 1 Physics of H2 and HD
- 2 Formation - Destruction
- 3 Observations and Models
- Non Stationary C-shocks: H2 Emission in Molecular Outflows
- The Ortho/Para Ratio in C and J-type Shocks
- Theoretical Models of Photodissociation Fronts
- ISO Spectroscopy of H2 in Star Forming Regions
- Observations of the H2 Ortho-Para Ratio in Photodissociation Regions
- H2 Emission from CRL618
- Hydrogen in Photodissociation Regions: NGC2023 and NGC7023
- A Pre-FUSE View of H2
- H2 Absorption Line Measurements with ORFEUS
- Ultraviolet Observations of Molecular Hydrogen in Interstellar Space
- FUSE and Deuterated Molecular Hydrogen
- ISO-SWS Observations of H2 in Galactic Sources
- H2 in Molecular Supernova Remnants
- 3D Integral Field H2 Spectroscopy in Outflows
- Near-Infrared Imaging and [OI] Spectroscopy of IC443 using 2MASS and ISO
- ISOCAM Spectro-imaging of the Supernova Remnant IC443
- Spatial Structure of a Photo-Dissociation Region in Ophiucus
- Tracing H2 Via Infrared Dust Extinction
- The Small Scale Structure of H2 Clouds
- Hot Chemistry in the Cold Diffuse Medium: Spectral Signature in the H2 Rotational Lines
- H2 Observations of the OMC-1 Outflow with the ISO-SWS
- 4 Extragalactic and Cosmology
- 5 Outlook
- Author index
Summary
Using the Short-Wavelength-Spectrometer on the Infrared Satellite Observatory (ISO), we obtained near- and mid-infrared spectra toward the brightest H2 emission peak of the Orion OMC-1 outflow. A wealth of emission and absorption features were detected, dominated by 60 H2 ro-vibrational and pure rotational lines reaching from H2 0–0 S(1) to 0–0 S(25).
The total H2 luminosity in the ISO-SWS aperture is (17 ± 5) L⊙, and extrapolated to the entire outflow, (120 ± 60) L⊙. The H2 level column density distribution shows no signs of fluorescent excitation or a deviation from an ortho-to-para ratio of three. It shows an excitation temperature which increases from about 600 K for the lowest rotational and vibrational levels to about 3200 K at level energies E(v, J)/k > 14 000 K.
Introduction
The Orion molecular cloud, OMC-1, located behind the Orion M42 Nebula at a distance of ∼450 pc (Genzel & Stutzki 1989), is the best-studied massive star forming region. This cloud embeds a spectacular outflow arising from some embedded young stellar object, which can possibly be identified as the radio source “I” 0.49 arcsec south of the infrared source IRc2-A (Menten & Reid 1995; Dougados et al. 1993). The outflow shocks the surrounding molecular gas, thereby giving rise to the strongest H2 infrared line emission appearing in the sky. Peak 1 (Beckwith et al. 1978) is the brighter of the two H2 emission lobes of the outflow. Although the outflow has been studied extensively for nearly two decades, the nature of the emission mechanism remains unclear.
- Type
- Chapter
- Information
- Molecular Hydrogen in Space , pp. 231 - 234Publisher: Cambridge University PressPrint publication year: 2000