APOGEE Chemical Abundance Patterns of the Massive Milky Way Satellites

Hasselquist, Sten; Hayes, Christian R.; Lian, Jianhui; Weinberg, David H.; Zasowski, Gail; Horta, Danny; Beaton, Rachael; Feuillet, Diane K.; Garro, Elisa R.; Gallart, Carme; Smith, Verne V.; Holtzman, Jon A.; Minniti, Dante; Lacerna, Ivan; Shetrone, Matthew; Jönsson, Henrik; Cioni, Maria-Rosa L.; Fillingham, Sean P.; Cunha, Katia; O’Connell, Robert; Fernández-Trincado, José G.; Muñoz, Ricardo R.; Schiavon, Ricardo; Almeida, Andres; Anguiano, Borja; Beers, Timothy C.; Bizyaev, Dmitry; Brownstein, Joel R.; Cohen, Roger E.; Frinchaboy, Peter; García-Hernández, D. A.; Geisler, Doug; Lane, Richard R.; Majewski, Steven R.; Nidever, David L.; Nitschelm, Christian; Povick, Joshua; Price-Whelan, Adrian; Roman-Lopes, Alexandre; Rosado, Margarita; Sobeck, Jennifer; Stringfellow, Guy; Valenzuela, Octavio; Villanova, Sandro; Vincenzo, Fiorenzo

Abstract

The SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey has obtained high-resolution spectra for thousands of red giant stars distributed among the massive satellite galaxies of the Milky Way (MW): the Large and Small Magellanic Clouds (LMC/SMC), the Sagittarius Dwarf Galaxy (Sgr), Fornax (Fnx), and the now fully disrupted Gaia Sausage/Enceladus (GSE) system. We present and analyze the APOGEE chemical abundance patterns of each galaxy to draw robust conclusions about their star formation histories, by quantifying the relative abundance trends of multiple elements (C, N, O, Mg, Al, Si, Ca, Fe, Ni, and Ce), as well as by fitting chemical evolution models to the [α/Fe]–[Fe/H] abundance plane for each galaxy. Results show that the chemical signatures of the starburst in the Magellanic Clouds (MCs) observed by Nidever et al. in the α-element abundances extend to C+N, Al, and Ni, with the major burst in the SMC occurring some 3–4 Gyr before the burst in the LMC. We find that Sgr and Fnx also exhibit chemical abundance patterns suggestive of secondary star formation epochs, but these events were weaker and earlier (∼5–7 Gyr ago) than those observed in the MCs. There is no chemical evidence of a second starburst in GSE, but this galaxy shows the strongest initial star formation as compared to the other four galaxies. All dwarf galaxies had greater relative contributions of AGB stars to their enrichment than the MW. Comparing and contrasting these chemical patterns highlight the importance of galaxy environment on its chemical evolution.

Citation

Hasselquist, S., Hayes, C. R., Lian, J., Weinberg, D. H., Zasowski, G., Horta, D., …Vincenzo, F. (2021). APOGEE Chemical Abundance Patterns of the Massive Milky Way Satellites. The Astrophysical journal, 923(2), Article 172. https://doi.org/10.3847/1538-4357/ac25f9

• Journal Article Type: Article
• Acceptance Date: Sep 10, 2021
• Online Publication Date: Dec 20, 2021
• Publication Date: Dec 1, 2021
• Deposit Date: Mar 12, 2022
• Journal: The Astrophysical Journal
• Print ISSN: 0004-637X
• Electronic ISSN: 1538-4357
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 923
• Issue: 2
• Article Number: 172
• DOI: https://doi.org/10.3847/1538-4357/ac25f9
• Keywords: Dwarf galaxies; Galaxies; Sagittarius dwarf spheroidal galaxy; Large Magellanic Cloud; Magellanic Clouds; Small Magellanic Cloud; Fornax dwarf spheroidal galaxy; Galaxy chemical evolution; Chemical enrichment; Chemical abundances; Abundance ratios; Galaxy
• Public URL: https://hull-repository.worktribe.com/output/3948233
• Related Public URLs: https://par.nsf.gov/biblio/10311777
• Additional Information: Article Title: APOGEE Chemical Abundance Patterns of the Massive Milky Way Satellites; Journal Title: The Astrophysical Journal; Article Type: paper; Copyright Information: © 2021. The American Astronomical Society. All rights reserved.; Date Received: 2021-07-19; Date Accepted: 2021-09-10; Online publication date: 2021-12-20