The Direct-Method Oxygen Abundance of Typical Dwarf Galaxies at Cosmic High-Noon

Abstract

We present a Keck/MOSFIRE, rest-optical, composite spectrum of 16 typical, gravitationally-lensed, star-forming, dwarf galaxies at $1.7\lesssim z\lesssim 2.6$ ($z_{\mathrm{mean}}=2.30$), all chosen independent of emission-line strength. These galaxies have a median stellar mass of $\log (M_{\ast }/{\mathrm{M}}_{\odot }{)}_{\mathrm{med}}=8.29_{-0.43}^{+0.51}$ and a median star formation rate of $\mathrm{SF}{\mathrm{R}}_{\mathrm{H}\alpha }^{\mathrm{med}}=2.25_{-1.26}^{+2.15}{\mathrm{M}}_{\odot }\mathrm{y}{\mathrm{r}}^{-1}$. We measure the faint, electron-temperature-sensitive, [O III] $\lambda$4363 emission line at $2.5\sigma$ ($4.1\sigma$) significance when considering a bootstrapped (statistical-only) uncertainty spectrum. This yields a direct-method oxygen abundance of $12+\log (O/H{)}_{\mathrm{direct}}=7.88_{-0.22}^{+0.25}$ ($0.15_{-0.06}^{+0.12}{\mathrm{Z}}_{\odot }$). We investigate the applicability at high-$z$ of locally-calibrated, oxygen-based, strong-line metallicity relations, finding that the local reference calibrations of arXiv:1805.08224 best reproduce ($\lesssim 0.12$ dex) our composite metallicity at fixed strong-line ratio. At fixed $M_{\ast }$, our composite is well-represented by the $z\sim 2.3$ direct-method stellar mass$-$gas-phase metallicity relation (MZR) of arXiv:1907.00013. When comparing to predicted MZRs from the IllustrisTNG and FIRE simulations, we find excellent agreement with the FIRE MZR. Our composite is consistent with no metallicity evolution, at fixed $M_{\ast }$ and SFR, of the locally-defined fundamental metallicity relation. We measure the doublet ratio [O II] $\lambda$3729/[O II] $\lambda 3726=1.56\pm 0.32$ ($1.51\pm 0.12$) and a corresponding electron density of $n_e=1_{-0}^{+215}\mathrm{c}{\mathrm{m}}^{-3}$ ($n_e=1_{-0}^{+74}\mathrm{c}{\mathrm{m}}^{-3}$) when considering the bootstrapped (statistical-only) error spectrum. This result suggests that lower-mass galaxies have lower densities than higher-mass galaxies at $z\sim 2$.

arXiv comment30 pages, 6 figures, 4 tables, abstract slightly abridged, use of PyNeb adopted (replacing use of IRAF) to calculate electron temperatures and densities; change in results is negligible, accepted for publication in ApJ

References in corpus (98)

• emcee: The MCMC Hammer
• Stellar population synthesis at the resolution of 2003
• Galactic Stellar and Substellar Initial Mass Function
• Star Formation in Galaxies Along the Hubble Sequence
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• The Host Galaxies of AGN
• The Origin of the Mass--Metallicity Relation: Insights from 53,000 Star-Forming Galaxies in the SDSS
• Theoretical Modeling of Starburst Galaxies
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics
• Simulating Galaxy Formation with the IllustrisTNG Model
• [O III]/[N II] as an Abundance Indicator at High Redshift
• A Highly Consistent Framework for the Evolution of the Star-Forming "Main Sequence" from z~0-6
• Galaxies on FIRE (Feedback In Realistic Environments): Stellar Feedback Explains Cosmologically Inefficient Star Formation
• Metallicity Calibrations and the Mass-Metallicity Relation for Star-Forming Galaxies
• Properties of galaxies reproduced by a hydrodynamic simulation
• Simulating galaxy formation with black hole driven thermal and kinetic feedback
• Using Strong Lines to Estimate Abundances in Extragalactic HII Regions and Starburst Galaxies
• A fundamental relation between mass, SFR and metallicity in local and high redshift galaxies
• Introducing the Illustris Project: the evolution of galaxy populations across cosmic time
• The Mass-Metallicity Relation at z~2
• An ultra-deep near-infrared spectrum of a compact quiescent galaxy at z=2.2
• AMAZE. I. The evolution of the mass-metallicity relation at z>3
• The MAPPINGS III Library of Fast Radiative Shock Models
• Constraining the Low-Mass Slope of the Star Formation Sequence at 0.5<z<2.5
• Cluster Lensing And Supernova survey with Hubble (CLASH): An Overview
• The chemical make-up of the Sun: A 2020 vision
• 3D-HST: A wide-field grism spectroscopic survey with the Hubble Space Telescope
• De Re Metallica: The cosmic chemical evolution of galaxies
• Stellar Population Inference with Prospector
• PyNeb: a new tool for analyzing emission lines. I. Code description and validation of results
• The chemical composition of metal-poor emission-line galaxies in the Data Release 3 of the Sloan Digital Sky Survey
• A Bayesian approach to strong lensing modelling of galaxy clusters
• The Frontier Fields: Survey Design
• Strong Nebular Line Ratios in the Spectra of z~2-3 Star-forming Galaxies: First Results from KBSS-MOSFIRE
• The Mass-Metallicity Relation with the Direct Method on Stacked Spectra of SDSS Galaxies
• Understanding Galaxy Evolution through Emission Lines
• An Analytic Model for the Evolution of the Stellar, Gas, and Metal Content of Galaxies
• The Origin of the Galaxy Mass-Metallicity Relation and Implications for Galactic Outflows
• The Spitzer Local Volume Legacy: Survey Description and Infrared Photometry
• Theoretical Evolution of Optical Strong Lines across Cosmic Time
• The MOSFIRE Deep Evolution Field (MOSDEF) Survey: Rest-Frame Optical Spectroscopy for ~1500 H-Selected Galaxies at 1.37 < z < 3.8
• The Origin and Evolution of the Galaxy Mass-Metallicity Relation
• On Extending the Mass-Metallicity Relation of Galaxies by 2.5 Decades in Stellar Mass
• Reconciling the Stellar and Nebular Spectra of High Redshift Galaxies
• A fundamental plane for field star-forming galaxies
• The Mass-Metallicity and the Fundamental Metallicity Relation revisited on a fully Te-based abundance scale for galaxies
• Direct Oxygen Abundances for Low Luminosity LVL Galaxies
• A physical model for cosmological simulations of galaxy formation: multi-epoch validation
• The Universal Relation of Galactic Chemical Evolution: The Origin of the Mass-Metallicity Relation
• The MOSDEF Survey: Electron Density and Ionization Parameter at $z\sim 2.3$
• Combining Strong and Weak Gravitational Lensing in Abell 1689
• New fully empirical calibrations of strong-line metallicity indicators in star forming galaxies
• New Strong Line Abundance Diagnostics for \HII Regions: Effects of $\kappa$-Distributed Electron Energies and New Atomic Data
• The MOSDEF Survey: The Evolution of the Mass-Metallicity Relation from $z=0$ to $z\sim 3.3$
• Nebular Emission Line Ratios in z~2-3 Star-Forming Galaxies with KBSS-MOSFIRE: Exploring the Impact of Ionization, Excitation, and Nitrogen-to-Oxygen Ratio
• The MOSDEF Survey: Mass, Metallicity, and Star-formation Rate at z~2.3
• The relation between metallicity, stellar mass and star formation in galaxies: an analysis of observational and model data
• The MOSDEF Survey: Excitation Properties of $z\sim 2.3$ Star-forming Galaxies
• The evolution of the mass-metallicity relation in IllustrisTNG
• Physical Properties of Emission-Line Galaxies at z ~ 2 from Near-Infrared Spectroscopy with Magellan FIRE
• The metallicity of the long GRB hosts and the Fundamental Metallicity Relation of low-mass galaxies
• The MOSDEF Survey: Direct-Method Metallicities and ISM Conditions at $z\sim 1.5-3.5$
• The Chemical Evolution of Star-Forming Galaxies Over the Last 11 Billion Years
• The FMOS-Cosmos Survey of Star-Forming Galaxies at z~1.6 II. The Mass-Metallicity Relation and the Dependence on Star Formation Rate and Dust Extinction
• The MOSDEF Survey: Dissecting the star-formation rate vs. stellar mass relation using H$\alpha$ and H$\beta$ emission lines at z ~ 2
• Ultra-faint Ultraviolet Galaxies at z~2 Behind the Lensing Cluster Abell 1689: the Luminosity Function, Dust Extinction and Star Formation Rate Density
• The MOSDEF survey: a stellar mass-SFR-metallicity relation exists at $z\sim 2.3$
• "Direct" Gas-Phase Metallicity in Local Analogs of High-Redshift Galaxies: Empirical Metallicity Calibrations for High-Redshift Star-Forming Galaxies
• The FMOS-COSMOS survey of star-forming galaxies at z~1.6. IV: Excitation state and chemical enrichment of the interstellar medium
• The MOSDEF Survey: Significant Evolution in the Rest-Frame Optical Emission Line Equivalent Widths of Star-Forming Galaxies at z=1.4-3.8
• Measuring the Physical Conditions in High-Redshift Star-Forming Galaxies: Insights from KBSS-MOSFIRE
• Gravitationally Lensed Galaxies at 2<z<3.5: Direct Abundance Measurements of Lya Emitters
• Low Masses and High Redshifts: The Evolution of the Mass-Metallicity Relation
• Star formation histories of UV-luminous galaxies at $z\simeq 6.8$: implications for stellar mass assembly at early cosmic times
• Fundamental metallicity relation in CALIFA, SDSS-IV MaNGA and high-z galaxies
• The CASSOWARY spectroscopy survey: A new sample of gravitationally lensed galaxies in SDSS
• The FMOS-COSMOS survey of star-forming galaxies at $z\sim 1.6$ VI: Redshift and emission-line catalog and basic properties of star-forming galaxies
• Strong-Lensing Analysis of MACS,J0717.5+3745 from Hubble Frontier Fields observations: How well can the mass distribution be constrained?
• The ALMA REBELS Survey: Specific Star-Formation Rates in the Reionization Era
• The COSMOS [OII] Survey: Evolution of Electron Density with Star Formation Rate
• The Evolution Of The Faint End Of The UV Luminosity Function During The Peak Epoch Of Star Formation (1<z<3)
• Hubble Frontier Fields: Predictions for the Return of SN Refsdal with the MUSE and GMOS Spectrographs
• Biases in metallicity measurements from global galaxy spectra: the effects of flux-weighting and diffuse ionized gas contamination
• A Tight Relation Between N/O Ratio and Galaxy Stellar Mass Can Explain the Evolution of Strong Emission Line Ratios with Redshift
• Temperature-based metallicity measurements at z=0.8: direct calibration of strong-line diagnostics at intermediate redshift
• Testing metallicity indicators at z~1.4 with the gravitationally lensed galaxy CASSOWARY 20
• 3D-HST Grism Spectroscopy of a Gravitationally Lensed, Low-metallicity Starburst Galaxy at z=1.847
• The MOSDEF Survey: Detection of [OIII]$\lambda$4363 and the direct-method oxygen abundance of a star-forming galaxy at z=3.08
• The metallicity evolution of low mass galaxies: New constraints at intermediate redshift
• Chemical abundance scaling relations for multiple elements in z~2-3 star-forming galaxies
• The KMOS${}^{3D}$ Survey: Investigating the Origin of the Elevated Electron Densities in Star-Forming Galaxies at $1\lesssim z\lesssim 3$
• The Ionizing Photon Production Efficiency (${\xi }_{ion}$) Of Lensed Dwarf Galaxies At $z\sim 2$
• The Detection of [O III]$\lambda$4363 in a Lensed, Dwarf Galaxy at $z$ = 2.59: Testing Metallicity Indicators and Scaling Relations at High Redshift and Low Mass
• Testing strong line metallicity diagnostics at z~2
• Stellar populations and star formation histories of the most extreme [OIII] emitters at $z=1.3-3.7$
• Reconciling the Results of the z~2 MOSDEF and KBSS-MOSFIRE Surveys

Cited by in corpus (2)

• A JWST/NIRSpec Exploration of the Connection between Ionization Parameter, Electron Density, and Star-Formation-Rate Surface Density in z=2.7-6.3 Galaxies
• Metallicity calibrations based on auroral lines from PHANGS-MUSE data