The [C ii]/[N ii] ratio in 3< z< 6 sub-millimetre galaxies from the South Pole Telescope survey
Affiliation
Univ Arizona, Steward ObservIssue Date
2020-03-30Keywords
galaxies: evolutiongalaxies: high-redshift
galaxies: statistics
submillimetre: galaxies
submillimetre: ISM
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OXFORD UNIV PRESSCitation
Cunningham, D. J. M., Chapman, S. C., Aravena, M., De Breuck, C., Béthermin, M., Chen, C. C., ... & Weiß, A. (2020). The [C ii]/[N ii] ratio in 3< z< 6 sub-millimetre galaxies from the South Pole Telescope survey. Monthly Notices of the Royal Astronomical Society, 494(3), 4090-4097.Rights
© 2020 The Author(s)Published by Oxford University Press on behalf of the Royal Astronomical Society.Collection Information
This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at repository@u.library.arizona.edu.Abstract
We present Atacama Compact Array and Atacama Pathfinder Experiment observations of the [N II] 205 mu m fine-structure line in 40 sub-millimetre galaxies lying at redshifts z = 3-6, drawn from the 2500 deg(2) South Pole Thlescope survey. This represents the largest uniformly selected sample of high-redshift [N II] 205 mu m measurements to date. 29 sources also have [C II] 158 mu m line observations allowing a characterization of the distribution of the [C II] to [N II] luminosity ratio for the first time at high redshift. The sample exhibits a median L[C II] /L [N II]) approximate to 11.0 and interquartile range of 5.0 -24.7. These ratios are similar to those observed in local (Ultra)luminous infrared galaxies (LIRGs), possibly indicating similarities in their interstellar medium. At the extremes, we find individual sub-millimetre galaxies with L[C II]/L [N II] low enough to suggest a smaller contribution from neutral gas than ionized gas to the [C II] flux and high enough to suggest strongly photon or X-ray region dominated flux. These results highlight a large range in this line luminosity ratio for sub-millimetre galaxies, which may be caused by variations in gas density, the relative abundances of carbon and nitrogen, ionization parameter, metallicity, and a variation in the fractional abundance of ionized and neutral interstellar medium.ISSN
0035-8711EISSN
1365-2966Version
Final published versionSponsors
National Science FoundationScopus Count
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