Astronomy and Astrophysics – Astronomy
Scientific paper
Aug 2000
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2000apj...539l..87m&link_type=abstract
The Astrophysical Journal, Volume 539, Issue 2, pp. L87-L91.
Astronomy and Astrophysics
Astronomy
39
Ism: Abundances, Ism: Individual: Name: Orion, Ism: Molecules
Scientific paper
We have obtained spectra of the rotational ground-state 110-101 556.936 GHz ortho-H216O and 110-101 547.676 GHz ortho-H218O transitions toward Orion BN/KL using the Submillimeter Wave Astronomy Satellite (SWAS). The ortho-H216O spectrum shows strong evidence for both a broad (Δv~=48 km s-1) and a narrow (Δv~=7.5 km s-1) component, while the ortho-H218O shows evidence for only a broad (Δv~=24 km s-1) component. The broad component emission in both ortho-H216O and ortho-H218O arises primarily from gas heated within the low- and high-velocity outflows and shocked gas surrounding IRc2 in which the ortho-H216O and ortho-H218O fractional abundances are estimated to be 3.5×10-4 and 7×10-7, respectively. This finding provides further confirmation that water is efficiently and abundantly produced within warm shock-heated gas. We estimate that the hot core plus the compact ridge contribute <~10% to the ortho-H216O integrated intensity within the SWAS beam. The narrow component seen in the ortho-H216O spectrum is best fitted by ortho-water emission from the extended ridge (ER) and the higher temperature core of the extended ridge (CER) with a common fractional abundance of 3.3×10-8. The absence of any discernible narrow component in the ortho-H218O spectrum is used to set 3 σ upper limits on the ortho-water fractional abundance within the ER of 7×10-8 and within the CER of 5.2×10-7. This implies that within the dense extended quiescent region, gas-phase water is neither a major repository of oxygen nor a major coolant in Orion BN/KL.
Ashby Matthew L. N.
Bergin Edwin A.
Chin Gordon
Erickson Neal R.
Goldsmith Paul F.
No associations
LandOfFree
Observations of Water Vapor toward Orion BN/KL does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Observations of Water Vapor toward Orion BN/KL, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observations of Water Vapor toward Orion BN/KL will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-735566