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Cited by 320

The DOI matches its Crossref record; 79 of the 79 references it cites were found in a registry or an index.

THE MOSDEF SURVEY: ELECTRON DENSITY AND IONIZATION PARAMETER AT z ∼ 2.3*

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Sanders, Ryan L., Shapley, Alice E., Kriek, Mariska, Reddy, Naveen A., Freeman, William R., Coil, Alison L., Siana, Brian, Mobasher, Bahram, Shivaei, Irene, Price, Sedona H., Groot, Laura de·2016·The Astrophysical Journal
DOI 10.3847/0004-637x/816/1/23
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Abstract

Using observations from the MOSFIRE Deep Evolution Field survey, we investigate the physical conditions of star-forming regions in z ∼ 2.3 galaxies, specifically the electron density and ionization state. From measurements of the [O ii]λλ 3726,3729 and [S ii]λλ 6716,6731 doublets, we find a median electron density of ∼250 cm−3 at z ∼ 2.3, an increase of an order of magnitude compared to measurements of galaxies at z ∼ 0. While z ∼ 2.3 galaxies are offset toward significantly higher O 32 values relative to local galaxies at fixed stellar mass, we find that the high-redshift sample follows a similar distribution to the low-metallicity tail of the local distribution in the O 32 versus R 23 and O3N2 diagrams. Based on these results, we propose that z ∼ 2.3 star-forming galaxies have the same ionization parameter as local galaxies at fixed metallicity. In combination with simple photoionization models, the position of local and z ∼ 2.3 galaxies in excitation diagrams suggests that there is no significant change in the hardness of the ionizing spectrum at fixed metallicity from z ∼ 0 to z ∼ 2.3. We find that z ∼ 2.3 galaxies show no offset compared to low-metallicity local galaxies in emission line ratio diagrams involving only lines of hydrogen, oxygen, and sulfur, but show a systematic offset in diagrams involving [N ii]λ 6584. We conclude that the offset of z ∼ 2.3 galaxies from the local star-forming sequence in the [N ii] BPT diagram is primarily driven by elevated N/O at fixed O/H compared to local galaxies. These results suggest that the local gas-phase and stellar metallicity sets the ionization state of star-forming regions at z ∼ 0 and z ∼ 2.

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Metadata

Authors
Sanders, R. L., Shapley, A. E., Kriek, M., Reddy, N. A., Freeman, W. R., Coil, A. L., Siana, B., Mobasher, B., Shivaei, I., Price, S. H., & Groot, L. D.
Venue
The Astrophysical Journal
Publisher
American Astronomical Society
Published
2015-12-28
Volume
816
Issue
1
Pages
23
ISSN
  • 0004-637X (ISSN-L)
  • 1538-4357
DOI
10.3847/0004-637x/816/1/23
OpenAlex
W2232844405
Cited by
320
References
79
FWCI
12.54
Type
journal article
Language
en
Open access
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CoChat. (2026). Citation check: THE MOSDEF SURVEY: ELECTRON DENSITY AND IONIZATION PARAMETER AT z ∼ 2.3*. https://app.cochat.ai/papers/10.3847/0004-637x/816/1/23
The paper
Sanders, R. L., Shapley, A. E., Kriek, M., Reddy, N. A., Freeman, W. R., Coil, A. L., Siana, B., Mobasher, B., Shivaei, I., Price, S. H., & Groot, L. D. (2016). THE MOSDEF SURVEY: ELECTRON DENSITY AND IONIZATION PARAMETER AT z ∼ 2.3*. The Astrophysical Journal. https://doi.org/10.3847/0004-637x/816/1/23

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.