Disc dichotomy signature in the vertical distribution of [Mg/Fe] and the delayed gas infall scenario

Abstract

The analysis of the APOGEE data suggests the existence of a clear distinction between two sequences of disc stars in the [$\alpha$/Fe] vs. [Fe/H] abundance ratio space. We aim to test if the two-infall chemical evolution models designed to reproduce these two sequences in the solar neighbourhood are also capable to predict the disc bimodality observed in the vertical distribution of [Mg/Fe] in APOGEE DR16 data. Along with the predicted chemical composition of SSPs born at different Galactic times in the solar vicinity, we provide their maximum vertical height |zmax| above the Galactic plane computed assuming the relation between the vertical action and stellar age in thin disc stars. The predicted vertical distribution of the [Mg/Fe] abundance ratio is in agreement with the one observed combining the APOGEE DR16 data and the astroNN catalogue (stellar ages, orbital parameters) for stars younger than 8 Gyr (only low-$\alpha$ sequence stars). Including the high-$\alpha$ disc component, the dichotomy in the vertical [Mg/Fe] abundance distribution is reproduced considering the observational cut in the Galactic height of |z| < 2 kpc. However, our model predicts a too flat growth of the |zmax| as a function of [Mg/Fe] for high-$\alpha$ objects in contrast with the median values from APOGEE data. Possible explanations for such a tension are: i) the data sample with |z| < 2 kpc is more likely contaminated by halo stars, causing the median values to be kinematically hotter, ii) external perturbations such as minor mergers could have heated up the disc, and the heating of the orbits cannot be modelled by only scattering processes. Assuming for the data a disc dissection based on chemistry, the observed |zmax| distributions for high-$\alpha$ and low-$\alpha$ sequences are in good agreement with our model predictions if we consider in the calculation the errors in the vertical action estimates.

arXiv commentAccepted for publication in Astronomy and Astrophysics (A&A), 17 pages, 15 figures

References in corpus (91)

• emcee: The MCMC Hammer
• The Structure of Cold Dark Matter Halos
• The Global Schmidt Law in Star Forming Galaxies
• galpy: A Python Library for Galactic Dynamics
• The Sixteenth Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra
• Nucleosynthesis in Chandrasekhar Mass Models for Type Ia Supernovae and Constraints on Progenitor Systems and Burning-Front Propagation
• The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
• Radial Mixing in Galactic Discs
• The Chemical Evolution of the Galaxy: the two-infall model
• Chemical evolution with radial mixing
• Chemical Cartography with APOGEE: Metallicity Distribution Functions and the Chemical Structure of the Milky Way Disk
• The GALAH+ Survey: Third Data Release
• Quantifying the Fragility of Galactic Disks in Minor Mergers
• Gaia Data Release 2: Mapping the Milky Way disc kinematics
• Quantifying the uncertainties of chemical evolution studies. II. Stellar yields
• Ages and fundamental properties of Kepler exoplanet host stars from asteroseismology
• A New Mechanism for Radial Migration in Galactic Disks: Spiral-Bar Resonance Overlap
• Chemical evolution with rotating massive star yields: I. The solar neighbourhood and the s-process elements
• Sinking Satellites and the Heating of Galaxy Discs
• Standing on the shoulders of Dwarfs: the Kepler asteroseismic LEGACY sample II - radii, masses, and ages
• Inside Out and Upside Down: Tracing the Assembly of a Simulated Disk Galaxy Using Mono-Age Stellar Populations
• Stars, Gas, and Dark Matter in the Solar Neighborhood
• The evolution of the Milky Way from its earliest phases : constraints on stellar nucleosynthesis
• The Genesis of the Milky Way's Thick Disk via Stellar Migration
• Chemodynamical Simulations of the Milky Way Galaxy
• The Gaia-ESO Survey: the Galactic Thick to Thin Disc transition
• Vertical density waves in the Milky Way disc induced by the Sagittarius Dwarf Galaxy
• Dynamical heating across the Milky Way disc using APOGEE and $Gaia$
• Thin disc, Thick Disc and Halo in a Simulated Galaxy
• Tracing chemical evolution over the extent of the Milky Way's Disk with APOGEE Red Clump Stars
• Evolution of Galactic Discs: Multiple Patterns, Radial Migration and Disc Outskirts
• Galactic Archaeology with asteroseismic ages: evidence for delayed gas infall in the formation of the Milky Way disc
• Distribution functions for the Milky Way
• On the origin of the chemical bimodality of disk stars: A tale of merger and migration
• NuGrid Stellar Data Set. II. Stellar Yields from H to Bi for Stellar Models with Mzams = 1 to 25Msun and Z = 0.0001 to 0.02
• From the bulge to the outer disc: StarHorse stellar parameters, distances, and extinctions for stars in APOGEE DR16 and other spectroscopic surveys
• VINTERGATAN I: The origins of chemically, kinematically and structurally distinct discs in a simulated Milky Way-mass galaxy
• Simultaneous calibration of spectro-photometric distances and the Gaia DR2 parallax zero-point offset with deep learning
• Cold Dark Matter Substructure and Galactic Disks II: Dynamical Effects of Hierarchical Satellite Accretion
• Chemical Cartography with APOGEE: Multi-element abundance ratios
• Origin of chemically distinct discs in the Auriga cosmological simulations
• Abundance gradients in the Milky Way for alpha elements, Iron peak elements, Barium, Lanthanum and Europium
• The Gaia-ESO Survey: Exploring the complex nature and origins of the Galactic bulge populations
• The Gaia-ESO Survey: the chemical structure of the Galactic discs from the first internal data release
• High-precision abundances of elements in solar-type stars. Evidence of two distinct sequences in abundance-age relations
• The GALAH survey: An abundance, age, and kinematic inventory of the solar neighbourhood made with TGAS
• All-Sky Dynamical Response of the Galactic Halo to the Large Magellanic Cloud
• Radial Migration in Galactic Thick Discs
• The Impact of Modeling Assumptions in Galactic Chemical Evolution Models
• The imprint of clump formation at high redshift. I. A disc alpha-abundance dichotomy
• Effects of radial flows on the chemical evolution of the Milky Way disk
• APOGEE DR16: a multi-zone chemical evolution model for the Galactic disc based on MCMC methods
• Stellar yields with rotation and their effect on chemical evolution models
• Excitation of coupled stellar motions in the Galactic Disk by orbiting satellites
• In the Galactic disk, stellar [Fe/H] and age predict orbits and precise [X/Fe]
• The vertical motion history of disk stars throughout the Galaxy
• Fast estimation of orbital parameters in Milky-Way-like potentials
• Fundamental relations for the velocity dispersion of stars in the Milky Way
• Galactic Archaeology with asteroseismic ages. II. Confirmation of a delayed gas infall using Bayesian analysis based on MCMC methods
• Stellar migrations and metal flows -- Chemical evolution of the thin disc of a simulated Milky Way analogous galaxy
• Abundance gradients in spiral disks: is the gradient inversion at high redshift real?
• Chemical evolution of the Milky Way: constraints on the formation of the thick and thin discs
• Disc Heating: Comparing the Milky Way with Cosmological Simulations
• Hydrodynamical simulations of Galactic fountains II: evolution of multiple fountains
• Bimodality of [α/Fe]-[Fe/H] distributions is a natural outcome of dissipative collapse and disc growth in Milky Way-type galaxies
• A large and pristine sample of standard candles across the Milky Way: ~100,000 red clump stars with 3% contamination
• The Rotation Curve, Mass Distribution and Dark Matter Content of the Milky Way from Classical Cepheids
• Hydrodynamical simulations of Galactic fountains I: evolution of single fountains
• Galactic fountains and their connection with high and intermediate velocity clouds
• The effect of stellar migration on Galactic chemical evolution: a heuristic approach
• The BAyesian STellar Algorithm (BASTA): a fitting tool for stellar studies, asteroseismology, exoplanets, and Galactic archaeology
• 2D chemical evolution model: the impact of galactic disc asymmetries on azimuthal chemical abundance variations
• The AMBRE project: Iron-peak elements in the solar neighbourhood
• Relaxation in N-body simulations of disk galaxies
• Effects of Galactic fountains and delayed mixing in the chemical evolution of the Milky Way
• Cold accretion flows and chemical bimodality of the Milky Way galaxy
• Age-chemical abundance structure of the Galaxy I: Evidence for a late accretion event in the outer disc at z ~ 0.6
• The galactic habitable zone of the Milky Way and M31 from chemical evolution models with gas radial flows
• The GALAH survey: properties of the Galactic disk(s) in the solar neighbourhood
• Mapping the Galactic Disk with the LAMOST and Gaia Red Clump Sample VII: the Stellar Disk Structure Revealed by the Mono-abundance Populations
• The Galactic habitable zone around M and FGK stars with chemical evolution models with dust
• Impact of cosmological satellites on the vertical heating of the Milky Way disc
• The distribution of [$\alpha$/Fe] in the Milky Way disc
• The Vertical Metallicity Gradient of the Milky Way Disk: Transitions in [a/Fe] Populations
• Dynamical model of the Milky Way using APOGEE and Gaia data
• The AMBRE Project: Solar neighbourhood chemodynamical constraints on Galactic disc evolution
• The history of stellar metallicity in a simulated disc galaxy
• High- and Low-$\alpha$ Disk Stars Separate Dynamically at all Ages
• Actions are weak stellar age indicators in the Milky Way disk
• An observational testbed for cosmological zoom-in simulations: constraining stellar migration in the solar cylinder using asteroseismology
• Modelling the chemical evolution of the Milky Way

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• Beyond the two-infall model I. Indications for a recent gas infall with Gaia DR3 chemical abundances
• The chemical signature of the Galactic spiral arms revealed by Gaia DR3
• Oxygen, sulfur, and iron radial abundance gradients of classical Cepheids across the Galactic thin disk
• (Re)mind the gap: a hiatus in star formation history unveiled by APOGEE DR17
• The APO-K2 Catalog. II. Accurate Stellar Ages for Red Giant Branch Stars across the Milky Way
• 2D chemical evolution models II. Effects of multiple spiral arm patterns on O, Eu, Fe and Ba abundance gradients
• Shaping Galactic Habitability: the impact of stellar migration and gas giants
• A chemical close-up of the main body of the Sagittarius dwarf galaxy
• The LEGARE Project. I. Chemical evolution model of the Nuclear Stellar Disc in a Bayesian framework