Abstract We present results from Atacama Large Millimeter/submillimeter Array (ALMA) 1.2 mm continuum observations of a sample of 27 star-forming galaxies at z = 2.1–2.5 from the MOSFIRE Deep Evolution Field survey with metallicity and star formation rate measurements from optical emission lines. Using stacks of Spitzer, Herschel, and ALMA photometry (rest frame ∼8–400 μ m), we examine the infrared (IR) spectral energy distributions (SED) of z ∼ 2.3 subsolar-metallicity (∼0.5 Z ⊙ ) luminous infrared galaxies (LIRGs). We find that the data agree well with an average template of higher-luminosity local low-metallicity dwarf galaxies (reduced χ 2 = 1.8). When compared with the commonly used templates for solar-metallicity local galaxies or high-redshift LIRGs and ultraluminous IR galaxies, even in the most favorable case (with reduced χ 2 = 2.8), the templates are rejected at >98% confidence. The broader and hotter IR SED of both the local dwarfs and high-redshift subsolar-metallicity galaxies may result from different grain properties or a harder/more intense ionizing radiation field that increases the dust temperature. The obscured star formation rate (SFR) indicated by the far-IR emission of the subsolar-metallicity galaxies is only ∼60% of the total SFR, considerably lower than that of the local LIRGsmore »
The MOSFIRE Deep Evolution Field Survey: Implications of the Lack of Evolution in the Dust Attenuation–Mass Relation to z ∼ 2*
We investigate the relationship between dust attenuation and stellar mass (
- Award ID(s):
- 2009313
- Publication Date:
- NSF-PAR ID:
- 10363274
- Journal Name:
- The Astrophysical Journal
- Volume:
- 926
- Issue:
- 2
- Page Range or eLocation-ID:
- Article No. 145
- ISSN:
- 0004-637X
- Publisher:
- DOI PREFIX: 10.3847
- Sponsoring Org:
- National Science Foundation
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