The dominant form of oxygen in cold molecular clouds is gas-phase carbon monoxide (CO) and ice-phase water (H2O). Yet, in planet-forming disks around young stars, gas-phase CO and H2O are less abundant relative to their interstellar medium values, and no other major oxygen-carrying molecules have been detected. Some astrochemical models predict that gas-phase molecular oxygen (O2) should be a major carrier of volatile oxygen in disks. We report a deep search for emission from the isotopologue16O18O (
- Award ID(s):
- 1907653
- NSF-PAR ID:
- 10356079
- Date Published:
- Journal Name:
- The Astrophysical Journal Letters
- Volume:
- 934
- Issue:
- 1
- ISSN:
- 2041-8205
- Page Range / eLocation ID:
- L14
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3847/2041-8213/ac7e55
