Predictions for Complex Distributions of Stellar Elemental Abundances in Low-Mass Galaxies
arXiv:2110.08287 · doi:10.1093/mnras/stac834
Abstract
We investigate stellar elemental abundance patterns at z = 0 in 8 low-mass (M_* = 10^6 - 10^9 M_sun) galaxies in the Feedback in Realistic Environments (FIRE-2) cosmological simulations. Using magnesium (Mg) as a representative alpha-element, we explore stellar abundance patterns in [Mg/Fe] versus [Fe/H], which follow an overall monotonic trend that evolved slowly over time. Beyond this, we explore 3 notable secondary features in enrichment (found in three different case-study galaxies) that arise from a galaxy merger or bursty star formation. First, we observe a secondary track with a lower [Mg/Fe] than the main trend. At z = 0, stars from this track are predominantly found within 2-6 kpc of the center; they were accreted in a 1:3 total-mass-ratio merger ~ 0.4 Gyr ago. Second, we find a distinct elemental bi-modality that forms following a strong burst in star formation in a galaxy at t_lookback ~ 10 Gyr. This burst quenched star formation for ~ 0.66 Gyr, allowing Ia supernovae to enrich the system with iron before star formation resumed. Third, we examine stripes in enrichment that run roughly orthogonal to the dominant [Mg/Fe] versus [Fe/H] trend; these stripes correspond to short bursts of star formation during which core-collapse supernovae enrich the surrounding medium with Mg (and Fe) on short timescales. If observed, these features would substantiate the utility of elemental abundances in revealing the assembly and star formation histories of dwarf galaxies. We explore the observability of these features for upcoming spectroscopic studies. Our results show that precise measurements of elemental abundance patterns can reveal critical events in the formation histories of low-mass galaxies.
arXiv commentv1: 14 pages, 8 figures. Submitted to MNRAS on Oct. 18th, 2021 | v2: 15 pages, 8 figures. Accepted by MNRAS on Mar. 17th, 2022
References in corpus (59)
- The chemical composition of the Sun
- On the variation of the Initial Mass Function
- The cosmological simulation code GADGET-2
- The James Webb Space Telescope
- The Rockstar Phase-Space Temporal Halo Finder and the Velocity Offsets of Cluster Cores
- Nucleosynthesis in Chandrasekhar Mass Models for Type Ia Supernovae and Constraints on Progenitor Systems and Burning-Front Propagation
- GIZMO: A New Class of Accurate, Mesh-Free Hydrodynamic Simulation Methods
- FIRE-2 Simulations: Physics versus Numerics in Galaxy Formation
- Nucleosynthesis Yields of Core-Collapse Supernovae and Hypernovae, and Galactic Chemical Evolution
- A New Calculation of the Ionizing Background Spectrum and the Effects of HeII Reionization
- Extragalactic Science, Cosmology and Galactic Archaeology with the Subaru Prime Focus Spectrograph (PFS)
- Two populations of progenitors for type Ia SNe?
- The Cosmic Baryon Cycle and Galaxy Mass Assembly in the FIRE Simulations
- Chemical yields from low- and intermediate-mass stars: model predictions and basic observational constraints
- Two distinct ancient components in the Sculptor Dwarf Spheroidal Galaxy: First Results from DART
- The Impact of Baryonic Physics on the Structure of Dark Matter Halos: the View from the FIRE Cosmological Simulations
- Breathing FIRE: How Stellar Feedback Drives Radial Migration, Rapid Size Fluctuations, and Population Gradients in Low-Mass Galaxies
- Simulations of the Magellanic Stream in a First Infall Scenario
- (Star)bursts of FIRE: observational signatures of bursty star formation in galaxies
- Star formation in a galactic outflow
- Complexity on Small Scales: The Metallicity Distribution of the Carina Dwarf Spheroidal Galaxy
- The origin of ultra diffuse galaxies: stellar feedback and quenching
- The Star Formation & Chemical Evolution History of the Fornax Dwarf Spheroidal Galaxy
- Modelling chemical abundance distributions for dwarf galaxies in the Local Group: the impact of turbulent metal diffusion
- Complexity on Small Scales III: Iron and alpha Element Abundances in the Carina Dwarf Spheroidal Galaxy
- Where are the most ancient stars in the Milky Way?
- Multi-Element Abundance Measurements from Medium-Resolution Spectra. IV. Alpha Element Distributions in Milky Way Dwarf Satellite Galaxies
- Chemical abundances in LMC stellar populations I. The Inner disk sample Based on observations collected at the VLT UT2 telescope
- Origin of chemically distinct discs in the Auriga cosmological simulations
- A profile in FIRE: resolving the radial distributions of satellite galaxies in the Local Group with simulations
- The Lazy Giants: APOGEE Abundances Reveal Low Star Formation Efficiencies in the Magellanic Clouds
- Pushing back the limits: detailed properties of dwarf galaxies in a LCDM universe
- Stellar Chemical Abundances: In Pursuit of the Highest Achievable Precision
- Widespread star formation inside galactic outflows
- Chemical Abundances in the Ultra-Faint Dwarf Galaxies Grus I and Triangulum II: Neutron-Capture Elements as a Defining Feature of the Faintest Dwarfs
- The Dual Origin of Stellar Halos II: Chemical Abundances as Tracers of Formation History
- Faint dwarfs as a test of DM models: WDM vs. CDM
- Stellar Abundances for Galactic Archaeology Database IV - Compilation of Stars in Dwarf Galaxies
- Chemistry and Kinematics of the Late-Forming Dwarf Irregular Galaxies Leo A, Aquarius, and Sagittarius DIG
- Detailed Abundances in the Ultra-faint Magellanic Satellites Carina II and III
- Dancing in the Dark: Uncertainty in ultra-faint dwarf galaxy predictions from cosmological simulations
- The Distribution of Alpha Elements in Andromeda Dwarf Galaxies
- Elemental Abundances in M31: The Kinematics and Chemical Evolution of Dwarf Spheroidal Satellite Galaxies
- Chemical signatures of the first star clusters
- A Relationship Between Stellar Metallicity Gradients and Galaxy Age in Dwarf Galaxies
- Formation and evolution of late-type dwarf galaxies. I. NGC 1705 and NGC 1569
- The challenge of simultaneously matching the observed diversity of chemical abundance patterns in cosmological hydrodynamical simulations
- A Predicted Correlation Between Age Gradient and Star Formation History in FIRE Dwarf Galaxies
- Dissecting the stellar content of Leo I: a dwarf irregular caught in transition
- Stars made in outflows may populate the stellar halo of the Milky Way
- The distinct stellar metallicity populations of simulated Local Group dwarfs
- Segue 1 - A Compressed Star Formation History Before Reionization
- Catalog of Chromium, Cobalt, and Nickel Abundances in Globular Clusters and Dwarf Galaxies
- Ultrafaint Dwarfs - Star Formation and Chemical Evolution in the Smallest Galaxies
- Forecasting Chemical Abundance Precision for Extragalactic Stellar Archaeology
- Progenitor-mass-dependent yields amplify intrinsic scatter in dwarf-galaxy elemental abundance ratios
- Chemical Abundances of Two Stars in the Large Magellanic Cloud Globular Cluster NGC~1718
- Understanding Dwarf Galaxies in order to Understand Dark Matter
- The Role of Dwarf Galaxies in Building Large Stellar Halos