Chemical Cartography with APOGEE: Mapping Disk Populations with a 2-process Model and Residual Abundances

Journal Article · Fri Jun 17 00:00:00 EDT 2022 · The Astrophysical Journal. Supplement Series

DOI:https://doi.org/10.3847/1538-4365/ac6028· OSTI ID:1983309

Weinberg, David H. ^[1]; Holtzman, Jon A. ^[2]; Johnson, Jennifer A. ^[3]; Hayes, Christian ^[4]; Hasselquist, Sten ^[5]; Shetrone, Matthew ^[6]; Ting, Yuan-Sen ^[7]; Beaton, Rachael L. ^[8]; Beers, Timothy C. ^[9]; Bird, Jonathan C. ^[10]; Bizyaev, Dmitry ^[11]; Blanton, Michael R. ^[12]; Cunha, Katia ^[13]; Fernández-Trincado, José G. ^[13]; Frinchaboy, Peter M. ^[14]; García-Hernández, D. A. ^[15]; Griffith, Emily ^[3]; Johnson, James W. ^[3]; Jönsson, Henrik ^[16]; Lane, Richard R. ^[17] ; Leung, Henry W. ^[18]; Mackereth, J. Ted ^[18]; Majewski, Steven R. ^[19]; Mészáros, Szabolcs ^[20]; Nitschelm, Christian ^[21]; Pan, Kaike ^[11]; Schiavon, Ricardo P. ^[22]; Schneider, Donald P. ^[23]; Schultheis, Mathias ^[24]; Smith, Verne ^[25]; Sobeck, Jennifer S. ^[4]; Stassun, Keivan G. ^[10]; Stringfellow, Guy S. ^[26]; Vincenzo, Fiorenzo ^[3]; Wilson, John C. ^[19]; Zasowski, Gail ^[5]

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1. The Ohio State University, Columbus, OH (United States); Institute for Advanced Study, Princeton, NJ (United States)
2. New Mexico State University, Las Cruces, NM (United States)
3. The Ohio State University, Columbus, OH (United States)
4. University of Washington, Seattle, WA (United States)
5. University of Utah, Salt Lake City, UT (United States)
6. University of California, Santa Cruz, CA (United States)
7. Institute for Advanced Study, Princeton, NJ (United States); Princeton University, NJ (United States); Observatories of the Carnegie Institution of Washington, Pasadena, CA (United States); Australian National University (Australia)
8. The Observatories of the Carnegie Institution for Science, Pasadena, CA (United States)
9. University of Notre Dame, IN (United States)
10. Vanderbilt University, Nashville, TN (United States)
11. Apache Point Observatory, Sunspot, NM (United States)
12. New York University, NY (United States)
13. Universidad de Atacama, Copiapo (Chile); Universidad Católica del Norte, Antofagasta (Chile)
14. Texas Christian University, Fort Worth, TX (United States)
15. Instituto de Astrofísica de Canarias, Tenerife (Spain); Universidad de La Laguna (ULL), Tenerife (Spain)
16. Malmö University (Sweden)
17. Universidad Bernardo O'Higgins, Santiago (Chile)
18. University of Toronto, ON (Canada)
19. University of Virginia, Charlottesville, VA (United States)
20. ELTE Eötvös Loránd University (Hungary); MTA-ELTE Lendület Milky Way Research Group (Hungary); MTA-ELTE Exoplanet Research Group (Hungary)
21. Universidad de Antofagasta (Chile)
22. Liverpool John Moores University (United Kingdom)
23. Pennsylvania State University, University Park, PA (United States)
24. Observatoire de la Côte d'Azur (France)
25. NSF's National Optical-Infrared Astronomy Research Laboratory, Tucson, AZ (United States)
26. University of Colorado, Boulder, CO (United States)

We apply a novel statistical analysis to measurements of 16 elemental abundances in 34,410 Milky Way disk stars from the final data release (DR17) of APOGEE-2. Building on recent work, we fit median abundance ratio trends [X/Mg] versus [Mg/H] with a 2-process model, which decomposes abundance patterns into a "prompt" component tracing core-collapse supernovae and a "delayed" component tracing Type Ia supernovae. For each sample star, we fit the amplitudes of these two components, then compute the residuals Δ[X/H] from this two-parameter fit. The rms residuals range from ~0.01–0.03 dex for the most precisely measured APOGEE abundances to ~0.1 dex for Na, V, and Ce. The correlations of residuals reveal a complex underlying structure, including a correlated element group comprised of Ca, Na, Al, K, Cr, and Ce and a separate group comprised of Ni, V, Mn, and Co. Selecting stars poorly fit by the 2-process model reveals a rich variety of physical outliers and sometimes subtle measurement errors. Residual abundances allow for the comparison of populations controlled for differences in metallicity and [α/Fe]. Relative to the main disk (R = 3–13 kpc), we find nearly identical abundance patterns in the outer disk (R = 15–17 kpc), 0.05–0.2 dex depressions of multiple elements in LMC and Gaia Sausage/Enceladus stars, and wild deviations (0.4–1 dex) of multiple elements in ω Cen. The residual abundance analysis opens new opportunities for discovering chemically distinctive stars and stellar populations, for empirically constraining nucleosynthetic yields, and for testing chemical evolution models that include stochasticity in the production and redistribution of elements.

• Research Organization: US Department of Energy (USDOE), Washington, DC (United States). Office of Science, Sloan Digital Sky Survey (SDSS)
• Sponsoring Organization: USDOE Office of Science (SC)
• OSTI ID: 1983309
• Journal Information: The Astrophysical Journal. Supplement Series, Journal Name: The Astrophysical Journal. Supplement Series Journal Issue: 2 Vol. 260; ISSN 0067-0049
• Publisher: IOP Publishing
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
Astronomy & Astrophysics
Galaxy chemical evolution
Milky Way disk
Stellar populations