APOGEE Chemical Abundances of the Sagittarius Dwarf Galaxy

Hasselquist, S.; Shetrone, Matthew D.; Smith, Verne V.; Cunha, Katia M. L.; McWilliam, Andrew; Holtzman, Jon A.; Majewski, Steven R.; Sobeck, Jennifer; Frinchaboy, Peter M.; Roman-Lopes, Alexandre; Ivans, Inese I.; Allende-Prieto, C.; Placco, Vinicius M.; Lane, Richard; Zasowski, Gail; APOGEE
Bibliographical reference

American Astronomical Society, AAS Meeting #229, id.123.04

Advertised on:
1
2017
Number of authors
16
IAC number of authors
1
Citations
0
Refereed citations
0
Description
The Apache Point Observatory Galactic Evolution Experiment (APOGEE) provides elemental abundances for C, N, O, Na, Mg, Al, Si, P, S, K, Ca, Ti, V, Cr, Mn, Fe, Co, and Ni. We analyze the chemical abundance patterns of these elements for ~ 350 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 in the dwarf galaxy. For Sgr stars with [Fe/H] > -0.9, we find that Sgr is deficient in all elemental abundance ratios (expressed as [X/Fe]) relative to the Milky Way, which suggests that Sgr stars observed today were formed from gas that was less enriched by both Type II and Type Ia SNe. By examining the relative deficiencies of the hydrostatic (O, Mg, and Al) and explosive (Si, K, and Mn) elements , we find support that previous generations of Sgr stars were formed with a top-light IMF, lacking the most massive stars that would normally pollute the ISM with the hydrostatic elements.