Nitrogen sulfide in giant molecular clouds
Publication Date
1997
Journal or Book Title
ASTROPHYSICAL JOURNAL
Abstract
We report a survey for nitrogen sulfide (NS) toward regions of massive star formation. NS was observed by means of its 2Π1/2, J = 3/2 → 1/2, J = 5/2 → 3/2, and J = 7/2 → 5/2 transitions at 69, 115, and 161 GHz, respectively, and was detected toward 12 of 14 giant molecular clouds (GMCs) observed. Analysis of the hyperfine component relative line strengths suggests that NS emission is optically thin toward these sources, with the possible exception of Sgr B2(M). The fractional abundance of NS relative to molecular hydrogen is best defined for the Orion molecular cloud, where it is typically (1-4) × 10-10, which is about an order of magnitude larger than found by some recent gas-phase chemistry models developed for quiescent clouds. Toward OMC-1, the NS integrated intensity is strongly peaked toward KL, but also extends all along the Orion ridge, resembling the distribution of SO and CH3OH. We have identified a spectral feature seen toward several sources as the ortho-NKK = 404 → 313, J = 3 → 2, fine-structure component of methylene (CH2; cf. Hollis, Jewell, & Lovas). We also report the first detection of the SO+2Π1/2, J = 3/2 → 1/2, parity-e transition toward W51(MS) and L134N.
DOI
https://doi.org/10.1086/303749
Pages
711-721
Volume
477
Issue
2
Recommended Citation
McGonagle, D and Irvine, William M., "Nitrogen sulfide in giant molecular clouds" (1997). ASTROPHYSICAL JOURNAL. 216.
https://doi.org/10.1086/303749
Comments
The published version is located at http://iopscience.iop.org/0004-637X/477/2/711