C iii] Emission in Star-forming Galaxies at z ∼ 1

Journal Article · Mon Mar 20 04:00:00 EDT 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/AA64CF· OSTI ID:22869175

Xinnan, Du; Shapley, Alice E. ^[1]; Martin, Crystal L. ^[2]; Coil, Alison L. ^[3]

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1. Department of Physics and Astronomy, University of California, Los Angeles, CA, 90095 (United States)
2. Department of Physics, University of California, Santa Barbara, CA, 93106 (United States)
3. Department of Physics, University of California, San Diego, CA, 92093 (United States)

The C iii]λλ1907, 1909 rest-frame UV emission doublet has recently been detected in galaxies during the epoch of reionization (z > 6), with a high equivalent width (EW; 10 Å, rest frame). Currently, it is possible to obtain much more detailed information for star-forming galaxies at significantly lower redshift. Accordingly, studies of their far-UV spectra are useful for understanding the factors modulating the strength of C iii] emission. We present the first statistical sample of C iii] emission measurements in star-forming galaxies at z ∼ 1. Our sample is drawn from the DEEP2 survey and spans the redshifts 0.64 ⩽ z ⩽ 1.35 (〈z〉=1.08). We find that the median EW of individual C iii] detections in our sample (1.30 Å) is much smaller than the typical value observed thus far at z > 6. Furthermore, out of 184 galaxies with coverage of C iii], only 40 have significant detections. Galaxies with individual C iii] detections have bluer colors and lower luminosities on average than those without, implying that strong C iii] emitters are in general young and low-mass galaxies without significant dust extinction. Using stacked spectra, we further investigate how C iii] strength correlates with multiple galaxy properties (M {sub B}, U − B, M {sub *}, star formation rate, specific star formation rate) and rest-frame near-UV (Fe ii* and Mg ii) and optical ([O iii] and Hβ) emission line strengths. These results provide a detailed picture of the physical environment in star-forming galaxies at z ∼ 1, and motivate future observations of strong C iii] emitters at similar redshifts.

• OSTI ID: 22869175
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 838; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COSMIC DUST
DETECTION
EMISSION
GALACTIC EVOLUTION
GALAXIES
HYDROGEN
LUMINOSITY
MASS
RED SHIFT
STAR EVOLUTION
STARS
ULTRAVIOLET RADIATION
ULTRAVIOLET SPECTRA