APOGEE Chemical Abundances of the Sagittarius Dwarf Galaxy

Abstract

The Apache Point Observatory Galactic Evolution Experiment (APOGEE) provides the opportunity to measure elemental abundances for C, N, O, Na, Mg, Al, Si, P, K, Ca, V, Cr, Mn, Fe, Co, and Ni in vast numbers of stars. We analyze the chemical abundance patterns of these elements for 158 red giant stars belonging to the Sagittarius dwarf galaxy (Sgr). This is the largest sample of Sgr stars with detailed chemical abundances and the first time C, N, P, K, V, Cr, Co, and Ni have been studied at high-resolution in this galaxy. We find that the Sgr stars with [Fe/H] $\gtrsim$ -0.8 are deficient in all elemental abundance ratios (expressed as [X/Fe]) relative to the Milky Way, suggesting that Sgr stars observed today were formed from gas that was less enriched by Type II SNe than stars formed in the Milky Way. By examining the relative deficiencies of the hydrostatic (O, Na, Mg, and Al) and explosive (Si, P, K, and Mn) elements, our analysis supports the argument that previous generations of Sgr stars were formed with a top-light IMF, one lacking the most massive stars that would normally pollute the ISM with the hydrostatic elements. We use a simple chemical evolution model, flexCE to further backup our claim and conclude that recent stellar generations of Fornax and the LMC could also have formed according to a top-light IMF.

14 pages, 12 figures, accepted for publication in ApJ

References in corpus (19)

• The 2.5 m Telescope of the Sloan Digital Sky Survey
• The Dawes Review 2: Nucleosynthesis and stellar yields of low and intermediate-mass single stars
• The nucleosynthesis of Al26 and Fe60 in solar metallicity stars extending in mass from 11 to 120 Msun: the hydrostatic and explosive contributions
• The Dual Origin of Stellar Halos
• The DART imaging and CaT survey of the Fornax Dwarf Spheroidal Galaxy
• The exotic chemical composition of the Sagittarius dwarf Spheroidal galaxy
• The ACS Survey of Galactic Globular Clusters: M54 and Young Populations in the Sagittarius Dwarf Spheroidal Galaxy
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: Variation of the Metallicity Distribution Function Along the Sagittarius Stream
• New H-band Stellar Spectral Libraries for the SDSS-III/APOGEE survey
• Carbon and oxygen abundances in stellar populations
• Chemical Abundances and Kinematics in Globular Clusters and Local Group Dwarf Galaxies and Their Implications for Formation Theories of the Galactic Halo
• VLT/FLAMES spectroscopy of red giant branch stars in the Fornax dwarf spheroidal galaxy
• Deep SDSS optical spectroscopy of distant halo stars I. Atmospheric parameters and stellar metallicity distribution
• Carbon in Red Giants in Globular Clusters and Dwarf Spheroidal Galaxies
• Chemical abundances in the nucleus of the Sagittarius dwarf spheroidal galaxy
• Oxygen enrichment in carbon-rich planetary nebulae
• The origin of low [alpha/Fe] ratios in extremely metal-poor stars
• Chemical trends in the Galactic Halo with APOGEE data
• The IGIMF and other IMFs in dSphs: the case of Sagittarius

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• What is the Milky Way outer halo made of? High resolution spectroscopy of distant red giants
• The Age-Metallicity-Specific Orbital Energy Relation for the Milky Way's Globular Cluster System Confirms the Importance of Accretion for Its Formation
• The metallicity distribution in the core of the Sagittarus dwarf spheroidal: minimising the metallicity biases
• Keck HIRES Spectroscopy of SkyMapper Commissioning Survey Candidate Extremely Metal-Poor Stars
• APOGEE-2S view of the globular cluster Patchick 125 (Gran 3). New metallicity and elemental abundances from high-resolution spectroscopy
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• Chemo-dynamical reconstruction of Milky Way globular cluster progenitors: Age-metallicity relations and the universality of multiple stellar populations
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