| Name | OT1_pgolds01_4 |
| Title | Molecular Oxygen in Orion |
| URL | http://archives.esac.esa.int/hsa/whsa-tap-server/data?retrieval_type=OBSERVATION&observation_id=1342244289&instrument_name=HIFI&product_level=LEVEL0&compress=true |
| DOI | https://doi.org/10.5270/esa-mmp20ci |
| Author | goldsmith, p. |
| Description | Observations carried out to date for the Herschel Oxygen Project (HOP) indicate that the abundance of a potentially major oxygen-bearing species, O2 (molecular oxygen), predicted to be as high as 1e-4, is less than 1e-7. One extremely interesting exception is Orion. We have 2 hours of integration on the 487 Ghz and 774 GHz O2 transitions, and see statistically significant emission in two velocity features, at ~ 6 km/s and ~ 12 km/s. These data were taken at the Peak 1 position of strong H2 vibrational emission, approximately 40 from the KL/hot core position. Plambeck and Wright (1987) found that the Peak A position near the hot core is a strong source of HDO emission at ~12 km/s. Since HDO is thought to be released from recently warmed grains, this may be intimately connected with the low O2 abundance being a result of atomic oxygen being frozen on cold grains and hydrogenated to water ice. When released after grain heating, it produces a significant gas-phase abundance of water and molecular oxygen. The HOP project did not include the KL/hot core position (Peak A is within 5) due to concerns about line confusion. However, data from the HEXOS survey confirms that the the O2 lines are in relatively windows, and shows O2 emission at the same 6 km/s and 12 km/s velocities. The line intensities are a factor ~ 5 stronger than at the H2 Peak 1 position, although noise is very large due to limited integration time. This suggests that the emission is from the hot core (6 km/s) and Peak A (12 km/s). We thus request 12 hours of time to carry out deep integrations at the frequencies of the 487, 774, and 1121 GHz, O2 lines, pointing at a position that includes the hot core and Peak A. This will confirm the identification as molecular oxygen (with three transitions at matching pair of velocities) and give a good handle on the temperature of the region producing O2 emission and its total column density. The total time requested is 12.1 hours. |
| Publication |
|
| Instrument | HIFI_HifiPoint_dbs |
| Temporal Coverage | 2012-04-13T10:05:06Z/2012-09-19T17:10:40Z |
| Version | SPG v14.2.0 |
| Mission Description | Herschel was launched on 14 May 2009! It is the fourth cornerstone mission in the ESA science programme. With a 3.5 m Cassegrain telescope it is the largest space telescope ever launched. It is performing photometry and spectroscopy in approximately the 55-671 µm range, bridging the gap between earlier infrared space missions and groundbased facilities. |
| Creator Contact | https://support.cosmos.esa.int/h®erschel/ |
| Date Published | 2013-03-19T16:11:39Z |
| Last Update | 2026-03-02 |
| Keywords | Herschel Space Observatory data, ESA Herschel mission dataset, far-infrared astronomy observations, submillimeter astronomy data, infrared space telescope observations, PACS photometer data, PACS spectrometer data, SPIRE photometer data, SPIRE Fourier transform spectrometer data, HIFI heterodyne spectroscopy data, far-infrared spectroscopy dataset, submillimeter spectral line observations, cold universe observations dataset, star formation infrared data, molecular cloud far-infrared observations, interstellar medium spectroscopy data, protoplanetary disk infrared observations, galaxy evolution far-infrared data, dust emission submillimeter observations, cosmic infrared background measurements, extragalactic infrared survey data, calibrated level 2 data products, FITS files astronomy, spectral cubes far-infrared, flux-calibrated maps, continuum photometry data, spectral energy distribution measurements, ESA Herschel Science Archive data |
| Publisher And Registrant | European Space Agency |
| Credit Guidelines | European Space Agency, goldsmith et al., 2013, 'Molecular Oxygen in Orion', SPG v14.2.0, European Space Agency, https://doi.org/10.5270/esa-mmp20ci |