Identifying Sagittarius Stream Stars by Their APOGEE Chemical Abundance Signatures

Simple item page
dc.contributor.authorHasselquist, Sten
dc.contributor.authorCarlin, Jeffrey L.
dc.contributor.authorHoltzman, Jon A.
dc.contributor.authorShetrone, Matthew
dc.contributor.authorHayes, Christian R.
dc.contributor.authorCunha, Katia
dc.contributor.authorSmith, Verne
dc.contributor.authorBeaton, Rachael L.
dc.contributor.authorSobeck, Jennifer
dc.contributor.authorAllende Prieto, Carlos
dc.contributor.authorMajewski, Steven R.
dc.contributor.authorAnguiano, Borja
dc.contributor.authorBizyaev, Dmitry
dc.contributor.authorGarcia-Hernandez, D. A.
dc.contributor.authorLane, Richard R.
dc.contributor.authorPan, Kaike
dc.contributor.authorNidever, David L.
dc.contributor.authorFernandez-Trincado, Jose. G.
dc.contributor.authorWilson, John C.
dc.contributor.authorZamora, Olga
dc.date.accessioned2025-01-23T21:17:41Z
dc.date.available2025-01-23T21:17:41Z
dc.date.issued2019
dc.description.abstractThe SDSS-IV Apache Point Observatory Galactic Evolution Experiment (APOGEE) survey provides precise chemical abundances of 18 chemical elements for similar to 176,000 red giant stars distributed over much of the Milky Way Galaxy (MW), and includes observations of the core of the Sagittarius dwarf spheroidal galaxy (Sgr). The APOGEE chemical abundance patterns of Sgr have revealed that it is chemically distinct from the MW in most chemical elements. We employ a k-means clustering algorithm to six-dimensional chemical space defined by [(C+N)/Fe], [O/Fe], [Mg/Fe], [Al/Fe], [Mn/Fe], and [Ni/Fe] to identify 62 MW stars in the APOGEE sample that have Sgr-like chemical abundances. Of the 62 stars, 35 have Gaia kinematics and positions consistent with those predicted by N-body simulations of the Sgr stream, and are likely stars that have been stripped from Sgr during the last two pericenter passages (<2 Gyr ago). Another 20 of the 62 stars exhibit chemical abundances indistinguishable from the Sgr stream stars, but are on highly eccentric orbits with median r(apo) similar to 25 kpc. These stars are likely the "accreted" halo population thought to be the result of a separate merger with the MW 8-11 Gyr ago. We also find one hypervelocity star candidate. We conclude that Sgr was enriched to [Fe/H] similar to -0.2 before its most recent pericenter passage. If the "accreted halo" population is from one major accretion event, then this progenitor galaxy was enriched to at least [Fe/H] similar to -0.6, and had a similar star formation history to Sgr before merging.
dc.fuente.origenWOS
dc.identifier.doi10.3847/1538-4357/aafdac
dc.identifier.eissn1538-4357
dc.identifier.issn0004-637X
dc.identifier.urihttps://doi.org/10.3847/1538-4357/aafdac
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/101163
dc.identifier.wosidWOS:000458369900005
dc.issue.numero1
dc.language.isoen
dc.revistaAstrophysical journal
dc.rightsacceso restringido
dc.subjectgalaxies: dwarf
dc.subjectgalaxies: individual (Sagittarius dSph)
dc.subjectgalaxies: stellar content
dc.titleIdentifying Sagittarius Stream Stars by Their APOGEE Chemical Abundance Signatures
dc.typeartículo
dc.volumen872
sipa.indexWOS
sipa.trazabilidadWOS;2025-01-12
Files
Collections
Artículos de revistas