First Census of Gas-phase Metallicity Gradients of Star-forming Galaxies in Overdense Environments at Cosmic Noon

Abstract

We report the first spatially resolved measurements of gas-phase metallicity radial gradients in star-forming galaxies in overdense environments at $z\gtrsim 2$. The spectroscopic data are acquired by the \mg\ survey, a Hubble Space Telescope (HST) cycle-28 medium program. This program is obtaining 45 orbits of WFC3/IR grism spectroscopy in the density peak regions of three massive galaxy protoclusters (BOSS 1244, BOSS 1542 and BOSS 1441) at $z=2-3$. Our sample in the BOSS 1244 field consists of 20 galaxies with stellar-mass ranging from $10^{9.0}$ to $10^{10.3}$ \Msun\ , star formation rate (SFR) from 10 to 240 \Msun\,yr${}^{-1}$, and global gas-phase metallicity (\oh) from 8.2 to 8.6. At $1\sigma$ confidence level, 2/20 galaxies in our sample show positive (inverted) gradients -- the relative abundance of oxygen increasing with galactocentric radius, opposite the usual trend. Furthermore, 1/20 shows negative gradients and 17/20 are consistent with flat gradients. This high fraction of flat/inverted gradients is uncommon in simulations and previous observations conducted in blank fields at similar redshifts. To understand this, we investigate the correlations among various observed properties of our sample galaxies. We find an anticorrelation between metallicity gradient and global metallicity of our galaxies residing in extreme overdensities, and a marked deficiency of metallicity in our massive galaxies as compared to their coeval field counterparts. We conclude that the cold-mode gas accretion plays an active role in shaping the chemical evolution of galaxies in the protocluster environments, diluting their central chemical abundance, and flattening/inverting their metallicity gradients.

13 pages, 6 figures, 1 table. Accepted for publication in ApJL

References in corpus (19)

• Cold streams in early massive hot haloes as the main mode of galaxy formation
• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• The Origin of the Galaxy Mass-Metallicity Relation and Implications for Galactic Outflows
• The MOSDEF Survey: The Evolution of the Mass-Metallicity Relation from $z=0$ to $z\sim 3.3$
• Metallicity gradients in local field star-forming galaxies: Insights on inflows, outflows, and the coevolution of gas, stars and metals
• AGN Emission Line Diagnostics and the Mass-Metallicity Relation up to Redshift z~2: the Impact of Selection Effects and Evolution
• The MOSDEF Survey: Optical AGN Diagnostics at z~2.3
• The KLEVER Survey: Spatially resolved metallicity maps and gradients in a sample of 1.2 < z < 2.5 lensed galaxies
• A relationship between specific star formation rate and metallicity gradient within z=1 galaxies from KMOS-HiZELS
• Gas-phase metallicity gradients of TNG50 star-forming galaxies
• The Chemical Evolution Carousel of Spiral Galaxies: Azimuthal Variations of Oxygen Abundance in NGC1365
• CLEAR: The Gas-Phase Metallicity Gradients of Star-Forming Galaxies at 0.6 < z < 2.6
• The Grism Lens-Amplified Survey from Space (GLASS) X. Sub-kpc resolution gas-phase metallicity maps at cosmic noon behind the Hubble Frontier Fields cluster MACS1149.6+2223
• An extremely young massive clump forming by gravitational collapse in a primordial galaxy
• Evidence for HI replenishment in massive galaxies through gas accretion from the cosmic web
• A Census of Sub-kiloparsec Resolution Metallicity Gradients in Star-forming Galaxies at Cosmic Noon from HST Slitless Spectroscopy
• The mass-metallicity relation at z~1-2 and its dependence on star formation rate
• The mass-metallicity relation at cosmic noon in overdense environments: first results from the MAMMOTH-Grism HST slitless spectroscopic survey
• Spectroscopic Confirmation of two Extremely Massive Protoclusters BOSS1244 and BOSS1542 at $z=2.24$

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• Direct-method metallicity gradients derived from spectral stacking with SDSS-IV MaNGA
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• Evolution of the radial ISM metallicity gradient in the Milky Way disk since redshift $\approx 3$
• Insights on Metal Enrichment and Environmental Effect at $z\approx 5-7$ with JWST ASPIRE/EIGER and Chemical Evolution Model
• MAMMOTH-MOSFIRE: Environmental Effects on Galaxy Interstellar Medium at $z\sim 2$
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