The fundamental metallicity relation emerges from the local anti-correlation between star formation rate and gas-phase metallicity existing in disk galaxies

Abstract

The fundamental metallicity relation (FMR) states that galaxies of the same stellar mass but larger star formation rate (SFR) tend to have smaller gas-phase metallicity (<Zg>). It is thought to be fundamental because it naturally arises from the stochastic feeding of star-formation from external metal-poor gas accretion, a process extremely elusive to observe but essential according the cosmological simulations of galaxy formation. In this letter, we show how the FMR emerges from the local anti-correlation between SFR surface density and Zg recently observed to exist in disk galaxies. We analytically derive the global FMR from the local law, and then show that both relations agree quantitatively when considering the star-forming galaxies of the MaNGA survey. Thus, understanding the FMR becomes equivalent to understanding the origin of the anti-correlation between SFR and metallicity followed by the set of star-forming regions of any typical galaxy. The correspondence between local and global laws is not specific of the FMR, so that a number of local relations should exist associated with known global relations.

Accepted for publication in ApJL. 6 pages and 3 figures

References in corpus (12)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• Cold streams in early massive hot haloes as the main mode of galaxy formation
• Overview of the SDSS-IV MaNGA Survey: Mapping Nearby Galaxies at Apache Point Observatory
• Clues to the Origin of the Mass-Metallicity Relation: Dependence on Star Formation Rate and Galaxy Size
• Star formation sustained by gas accretion
• A Critical Look at the Mass-Metallicity-SFR Relation in the Local Universe. I. An Improved Analysis Framework and Confounding Systematics
• The SAMI Galaxy Survey: Exploring the gas-phase Mass-Metallicity Relation
• SDSS-IV MaNGA: What Shapes The Distribution Of Metals In Galaxies? Exploring The Roles Of The Local Gas Fraction And Escape Velocity
• Anomalously low metallicity regions in MaNGA star-forming galaxies: Accretion Caught in Action?
• The mass-metallicity relation of Lyman-break analogues and its dependence on galaxy properties
• On the 3D structure of the mass, metallicity, and SFR space for SF galaxies

Cited by in corpus (14)

• The ALMaQUEST Survey: V. The non-universality of kpc-scale star formation relations and the factors that drive them
• The metallicity's fundamental dependence on both local and global galactic quantities
• Metallicity Gradient of Barred Galaxies with TYPHOON
• The Evolution of Gas-Phase Metallicity and Resolved Abundances in Star-forming Galaxies at $z\approx 0.6-1.8$
• Stellar mass, not dynamical mass nor gravitational potential, drives the mass-metallicity relationship
• SDSS-IV MaNGA: galaxy gas-phase metallicity gradients vary across the mass-size plane
• How well do local relations predict gas-phase metallicity gradients? Results from SDSS-IV MaNGA
• Local and global gas metallicity versus stellar age relation in MaNGA galaxies
• SDSS-IV/MaNGA: Can impulsive gaseous inflows explain steep oxygen abundance profiles \& anomalously-low-metallicity regions?
• The Chocolate Chip Cookie Model: dust-to-metal ratio of HII regions
• Fundamental relation in isolated galaxies, pairs, and triplets in the local universe
• Both Stellar Mass and Gravitational Potential Shape the Gas-Phase Metallicity
• MASCOT: Molecular gas depletion times and metallicity gradients -- evidence for feedback in quenching active galaxies
• The extension of the Fundamental Metallicity Relation beyond the BPT star-forming sequence: evidence for both gas accretion and starvation