An Updated Dust-to-Star Geometry: Dust Attenuation Does Not Depend on Inclination in $1.3\le z\le 2.6$ Star-Forming Galaxies from MOSDEF

Abstract

We investigate dust attenuation and its dependence on viewing angle for 308 star-forming galaxies at $1.3\le z\le 2.6$ from the MOSFIRE Deep Evolution Field (MOSDEF) survey. We divide galaxies with a detected H$\alpha$ emission line and coverage of H$\beta$ into eight groups by stellar mass, star formation rate (SFR), and inclination (i.e., axis ratio), then stack their spectra. From each stack, we measure Balmer decrement and gas-phase metallicity, then we compute median \AV and UV continuum spectral slope ($\beta$). First, we find that none of the dust properties (Balmer decrement, \AV, $\beta$) vary with axis ratio. Second, both stellar and nebular attenuation increase with increasing galaxy mass, showing little residual dependence on SFR or metallicity. Third, nebular emission is more attenuated than stellar emission, and this difference grows even larger at higher galaxy masses and SFRs. Based on these results, we propose a three-component dust model where attenuation predominantly occurs in star-forming regions and large, dusty star-forming clumps, with minimal attenuation in the diffuse ISM. In this model, nebular attenuation primarily originates in clumps, while stellar attenuation is dominated by star-forming regions. Clumps become larger and more common with increasing galaxy mass, creating the above mass trends. Finally, we argue that a fixed metal yield naturally leads to mass regulating dust attenuation. Infall of low-metallicity gas increases SFR and lowers metallicity, but leaves dust column density mostly unchanged. We quantify this idea using the Kennicutt-Schmidt and fundamental metallicity relations, showing that galaxy mass is indeed the primary driver of dust attenuation.

19 pages, 13 figures, accepted for publication in ApJ

References in corpus (19)

• The propagation of uncertainties in stellar population synthesis modeling I: The relevance of uncertain aspects of stellar evolution and the IMF to the derived physical properties of galaxies
• An ultra-deep near-infrared spectrum of a compact quiescent galaxy at z=2.2
• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• Detection of quiescent galaxies in a bicolor sequence from z=0-2
• Constraining the Low-Mass Slope of the Star Formation Sequence at 0.5<z<2.5
• From rings to bulges: evidence for rapid secular galaxy evolution at z~2 from integral field spectroscopy in the SINS survey
• Strong Nebular Line Ratios in the Spectra of z~2-3 Star-forming Galaxies: First Results from KBSS-MOSFIRE
• The MOSFIRE Deep Evolution Field (MOSDEF) Survey: Rest-Frame Optical Spectroscopy for ~1500 H-Selected Galaxies at 1.37 < z < 3.8
• What do we learn from IRAC observations of galaxies at 2 < z < 3.5?
• The MOSDEF Survey: Mass, Metallicity, and Star-formation Rate at z~2.3
• Metallicities and Physical Conditions in Star-forming Galaxies at z~1.0-1.5
• Observations of Thick Disks in the Hubble Space Telescope Ultra Deep Field
• Sub-kpc ALMA imaging of compact star-forming galaxies at z~2.5: revealing the formation of dense galactic cores in the progenitors of compact quiescent galaxies
• The MOSDEF Survey: Optical AGN Diagnostics at z~2.3
• z~2: An Epoch of Disk Assembly
• The MOSDEF survey: AGN multi-wavelength identification, selection biases and host galaxy properties
• Characterizing Dust Attenuation in Local Star Forming Galaxies: Inclination Effects and the 2175Å Feature
• The First Robust Constraints on the Relationship Between Dust-to-Gas Ratio and Metallicity in Luminous Star-forming Galaxies at High Redshift
• The MOSDEF Survey: Probing Resolved Stellar Populations at $z\sim 2$ Using a New Bayesian-defined Morphology Metric Called Patchiness

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