Stellar Abundances for Galactic Archaeology Database IV - Compilation of Stars in Dwarf Galaxies

Abstract

We have constructed the database of stars in the local group using the extended version of the SAGA (Stellar Abundances for Galactic Archaeology) database that contains stars in 24 dwarf spheroidal galaxies and ultra faint dwarfs. The new version of the database includes more than 4500 stars in the Milky Way, by removing the previous metallicity criterion of [Fe/H] <= -2.5, and more than 6000 stars in the local group galaxies. We examined a validity of using a combined data set for elemental abundances. We also checked a consistency between the derived distances to individual stars and those to galaxies in the literature values. Using the updated database, the characteristics of stars in dwarf galaxies are discussed. Our statistical analyses of alpha-element abundances show that the change of the slope of the [alpha/Fe] relative to [Fe/H] (so-called "knee") occurs at [Fe/H] = -1.0+-0.1 for the Milky Way. The knee positions for selected galaxies are derived by applying the same method. Star formation history of individual galaxies are explored using the slope of the cumulative metallicity distribution function. Radial gradients along the four directions are inspected in six galaxies where we find no direction dependence of metallicity gradients along the major and minor axes. The compilation of all the available data shows a lack of CEMP-s population in dwarf galaxies, while there may be some CEMP-no stars at [Fe/H] <~ -3 even in the very small sample. The inspection of the relationship between Eu and Ba abundances confirms an anomalously Ba-rich population in Fornax, which indicates a pre-enrichment of interstellar gas with r-process elements. We do not find any evidence of anti-correlations in O-Na and Mg-Al abundances, which characterises the abundance trends in the Galactic globular clusters.

48 pages in single column format, 14 figures, accepted by PASJ. The SAGA database is available at http://sagadatabase.jp

References in corpus (42)

• alpha-, r-, and s-process element trends in the Galactic thin and thick disks
• Carbon Enhanced Metal-Poor Stars. I. Chemical Compositions of 26 Stars
• The Star Formation Histories of Local Group Dwarf Galaxies I. Hubble Space Telescope / Wide Field Planetary Camera 2 Observations
• First stars VI - Abundances of C, N, O, Li, and mixing in extremely metal-poor giants. Galactic evolution of the light elements
• Carbon-Enhanced Metal-Poor Star Frequencies in the Galaxy: Corrections for the Effect of Evolutionary Status on Carbon Abundances
• The DART imaging and CaT survey of the Fornax Dwarf Spheroidal Galaxy
• The exotic chemical composition of the Sagittarius dwarf Spheroidal galaxy
• The NIR Ca II triplet at low metallicity - Searching for extremely low-metallicity stars in classical dwarf galaxies
• A high resolution VLT/FLAMES study of individual stars in the centre of the Fornax dwarf spheroidal galaxy
• Segue 1: An Unevolved Fossil Galaxy from the Early Universe
• The Chemical Evolution of the Draco Dwarf Spheroidal Galaxy
• Analysis and calibration of CaII triplet spectroscopy of Red Giant Branch stars from VLT/FLAMES observations
• The Frequency of Carbon-Enhanced Metal-Poor Stars in the Galaxy from the HERES sample
• The intermediate neutron-capture process and carbon-enhanced metal-poor stars
• Observational Constraints on First-Star Nucleosynthesis. I. Evidence for Multiple Progenitors of CEMP-no Stars
• Multi-Element Abundance Measurements from Medium-Resolution Spectra. II. Catalog of Stars in Milky Way Dwarf Satellite Galaxies
• The Highly Unusual Chemical Composition of the Hercules Dwarf Spheroidal Galaxy
• TOPoS: II. On the bimodality of carbon abundance in CEMP stars. Implications on the early chemical evolution of galaxies
• Binarity in Carbon-Enhanced Metal-Poor stars
• Complexity on Small Scales III: Iron and alpha Element Abundances in the Carina Dwarf Spheroidal Galaxy
• Multi-Element Abundance Measurements from Medium-Resolution Spectra. IV. Alpha Element Distributions in Milky Way Dwarf Satellite Galaxies
• Looking outside the Galaxy: the discovery of chemical anomalies in 3 old Large Magellanic Cloud clusters
• Carbon Stars in the Hamburg/ESO Survey: Abundances
• A spectroscopic confirmation of the Bootes II dwarf spheroidal
• Triangulum II: Not Especially Dense After All
• VLT/FLAMES spectroscopy of red giant branch stars in the Fornax dwarf spheroidal galaxy
• High-resolution spectroscopy of RGB stars in the Sagittarius Streams. I. Radial velocities and chemical abundances
• The first carbon-enhanced metal-poor star found in the Sculptor dwarf spheroidal
• Complexity on Small Scales II: Metallicities and Ages in the Leo II Dwarf Spheroidal Galaxy
• Detailed Abundances of Two Very Metal-Poor Stars in Dwarf Galaxies
• Carbon in Red Giants in Globular Clusters and Dwarf Spheroidal Galaxies
• Chemical Signatures of the First Supernovae in the Sculptor Dwarf Spheroidal Galaxy
• Insights from the Outskirts: Chemical and Dynamical Properties in the outer Parts of the Fornax Dwarf Spheroidal Galaxy
• Chemical Abundances of the Leo II Dwarf Galaxy
• The Chemical Abundances of the Stellar Populations in the Leo I and Leo II dSph Galaxies
• Discovery of Super-Li Rich Red Giants in Dwarf Spheroidal Galaxies
• A chemical confirmation of the faint Bootes II dwarf Spheroidal Galaxy
• Gemini/GRACES Spectroscopy of Stars in Triangulum II
• An inefficient dwarf: Chemical abundances and the evolution of the Ursa Minor dwarf spheroidal galaxy
• Chemical Feature of Eu abundance in the Draco dwarf spheroidal galaxy
• Infrared High-Resolution Integrated Light Spectral Analyses of M31 Globular Clusters from APOGEE
• Color-Magnitude Diagram Constraints on the Metallicities, Ages, and Star Formation History of the Stellar Populations in the Carina Dwarf Spheroidal Galaxy

Cited by in corpus (62)

• Current Status of r-Process Nucleosynthesis
• Stellar Yields of Rotating First Stars. II. Pair Instability Supernovae and Comparison with Observations
• Pushing back the limits: detailed properties of dwarf galaxies in a LCDM universe
• Four-hundred Very Metal-Poor Stars Studied with LAMOST and Subaru. II. Elemental abundances
• The $R$-Process Alliance: Fourth Data Release from the Search for $r$-Process-Enhanced Stars in the Galactic Halo
• Origin of the excess of high-energy retrograde stars in the Galactic halo
• Magnetorotational supernovae: A nucleosynthetic analysis of sophisticated 3D models
• Metal-poor star formation triggered by the feedback effects from Pop III stars
• Pristine IX: CFHT ESPaDOnS Spectroscopic Analysis of 115 Bright Metal-Poor Candidate Stars
• The chemical evolution of r-process elements from neutron star mergers: the role of a 2-phase interstellar medium
• Enrichment of Zinc in galactic chemodynamical evolution models
• Zero and extremely low metallicity rotating massive stars: evolution, explosion, and nucleosynthesis up to the heaviest nuclei
• Evidence for the accretion origin of halo stars with an extreme r-process enhancement
• Neutron Star Mergers Are the Dominant Source of the r-process in the Early Evolution of Dwarf Galaxies
• The Most Metal-poor Stars in the Magellanic Clouds are $r$-process Enhanced
• High-precision chemical abundances of Galactic building blocks. The distinct chemical abundance sequence of Sequoia
• The morphology and structure of stellar populations in the Fornax dwarf spheroidal galaxy from Dark Energy Survey Data
• The Pristine Dwarf-Galaxy survey -- IV. Probing the outskirts of the dwarf galaxy Boötes I
• Detailed abundance analysis of globular clusters in the Local Group: NGC 147, NGC 6822, and Messier 33
• Origin of highly $r$-process-enhanced stars in a cosmological zoom-in simulation of a Milky Way-like galaxy
• Primordial nucleosynthesis with varying fundamental constants: Solutions to the Lithium problem and the Deuterium discrepancy
• Abundance Patterns of $\alpha$ and Neutron-capture Elements in the Helmi Stream
• Simulating Metal Mixing of Both Common and Rare Enrichment Sources in a Low Mass Dwarf Galaxy
• Catalog of Chromium, Cobalt, and Nickel Abundances in Globular Clusters and Dwarf Galaxies
• Extreme r-process enhanced stars at high metallicity in Fornax
• Enrichment of Strontium in Dwarf Galaxies
• LAMOST J2217+2104: a new member of carbon-enhanced extremely metal-poor stars with excesses of Mg and Si
• Are Faint Supernovae Responsible for Carbon-Enhanced Metal-Poor Stars?
• Evidence for r-process delay in very metal-poor stars
• Evidences of extragalactic origin and planet engulfment in the metal-poor twin pair HD 134439/HD 134440
• A-SLOTH reveals the nature of the first stars
• Forecasting Chemical Abundance Precision for Extragalactic Stellar Archaeology
• True Pair-instability Supernova Descendant: Implications for the First Stars' Mass Distribution
• Extending the Chemical Reach of the H3 Survey: Detailed Abundances of the Dwarf-galaxy Stellar Stream Wukong/LMS-1
• Fates of the oldest intermediate-mass stars - Primordial to Extremely Metal-Poor AGB and Super-AGB Stars: White Dwarf or Supernova progenitors
• Inferring the velocity of early massive stars from the abundances of extremely metal-poor stars
• Probing the early Milky Way with GHOST spectra of an extremely metal-poor star in the Galactic disk
• Can Population III stars be major origins of both merging binary black holes and extremely metal poor stars?
• The stochastic enrichment of Population II stars
• Nucleosynthetic yields of Z=$10^{-5}$ intermediate-mass stars
• High-speed stars. II. An unbound star, young stars, bulge metal-poor stars, and Aurora candidates
• s-process Enirchment of Ultrafaint Dwarf Galaxies
• Matter accretion in metal-poor stars down to extremely metal-poor stars and the lithium problem
• Neutron-capture elements in dwarf galaxies III: A homogenized analysis of 13 dwarf spheroidal and ultra-faint galaxies
• The formation of the Milky Way halo and its dwarf satellites: a NLTE-1D abundance analysis. IV. Segue 1, Triangulum II, and Coma Berenices UFDs
• The Chemical Composition of Extreme-Velocity Stars
• The heavy-elements heritage of the falling sky
• Stellar Loci VI: An Updated Catalog of the Best and Brightest Metal-poor Stars
• Predictions for Complex Distributions of Stellar Elemental Abundances in Low-Mass Galaxies
• A Modified Initial Mass Function of the First Stars with Explodability Theory under Different Enrichment Scenarios
• The oldest stars with low neutron-capture element abundances and origins in ancient dwarf galaxies
• A Catalog of 12,766 Carbon-enhanced Metal-poor Stars from LAMOST Data Release 8
• High speed stars: III. Detailed abundances and binary nature of the extreme speed star GHS143
• The Chemodynamical Nature of the Triangulum-Andromeda Overdensity
• M3DIS -- A grid of 3D radiation-hydrodynamics stellar atmosphere models for stellar surveys. II. Carbon-enhanced metal-poor stars
• First Star Survivors as Metal-Rich Halo Stars that Experienced Supernova Explosions in Binary Systems
• Comparing simulated Milky Way satellite galaxies with observations using unsupervised clustering
• Searching for Low-mass Population III Stars Disguised as White Dwarfs
• Main-sequence Turnoff Stars as Probes of the Ancient Galactic Relic: Chemo-dynamical Analysis of a Pilot Sample
• The metal-poor tail of the APOGEE survey I. Uncovering [Fe/H] < -2.5 stars from the inner Galaxy to the Magellanic Clouds
• HR-GO II: chemical abundances of low-$E$ retrograde dynamically-tagged-groups: Revealing Thamnos as a very metal-poor substructure
• A comparative study on three modes of s-process nucleosynthesis in extremely metal-poor AGB stars