How many components? Quantifying the complexity of the metallicity distribution in the Milky Way bulge with APOGEE

Simple item page
dc.contributor.authorRojas-Arriagada, Alvaro
dc.contributor.authorZasowski, Gail
dc.contributor.authorSchultheis, Mathias
dc.contributor.authorZoccali, Manuela
dc.contributor.authorHasselquist, Sten
dc.contributor.authorChiappini, Cristina
dc.contributor.authorCohen, Roger E.
dc.contributor.authorCunha, Katia
dc.contributor.authorFernandez-Trincado, Jose G.
dc.contributor.authorFragkoudi, Francesca
dc.contributor.authorGarcia-Hernandez, D. A.
dc.contributor.authorGeisler, Doug
dc.contributor.authorGran, Felipe
dc.contributor.authorLian, Jianhui
dc.contributor.authorMajewski, Steven
dc.contributor.authorMinniti, Dante
dc.contributor.authorMonachesi, Antonela
dc.contributor.authorNitschelm, Christian
dc.contributor.authorQueiroz, Anna B. A.
dc.date.accessioned2025-01-23T19:47:38Z
dc.date.available2025-01-23T19:47:38Z
dc.date.issued2020
dc.description.abstractWe use data of similar to 13 000 stars from the Sloan Digital Sky Survey/Apache Point Observatory Galactic Evolution Experiment survey to study the shape of the bulge metallicity distribution function (MDF) within the region vertical bar l vertical bar <= 11 degrees and vertical bar b vertical bar = 13 degrees, and spatially constrained to R-GC <= 3.5 kpc. We apply Gaussian mixture modelling and non-negative matrix factorization decomposition techniques to identify the optimal number and the properties of MDF components. We find that the shape and spatial variations of the MDF (at [Fe/H] >= -1 dex) are well represented as a smoothly varying contribution of three overlapping components located at [Fe/H] = +0.32, -0.17, and -0.66 dex. The bimodal MDF found in previous studies is in agreement with our trimodal assessment once the limitations in sample size and individual measurement errors are taken into account. The shape of the MDF and its correlations with kinematics reveal different spatial distributions and kinematical structure for the three components co-existing in the bulge region. We confirm the consensus physical interpretation of metal-rich stars as associated with the secularly evolved disc into a boxy/peanut X-shape bar. On the other hand, metal-intermediate stars could be the product of in-situ formation at high redshift in a gas-rich environment characterized by violent and fast star formation. This interpretation would help us to link a present-day structure with those observed in formation in the centre of high-redshift galaxies. Finally, metal-poor stars may correspond to the metal-rich tail of the population sampled at lower metallicity from the study of RR Lyrae stars. Conversely, they could be associated with the metal-poor tail of the early thick disc.
dc.fuente.origenWOS
dc.identifier.doi10.1093/mnras/staa2807
dc.identifier.eissn1365-2966
dc.identifier.issn0035-8711
dc.identifier.urihttps://doi.org/10.1093/mnras/staa2807
dc.identifier.urihttps://repositorio.uc.cl/handle/11534/100397
dc.identifier.wosidWOS:000587761200076
dc.issue.numero1
dc.language.isoen
dc.pagina.final1057
dc.pagina.inicio1037
dc.revistaMonthly notices of the royal astronomical society
dc.rightsacceso restringido
dc.subjectinfrared: stars
dc.subjectstars: fundamental parameters
dc.subjectstars: abundances
dc.subjectGalaxy: bulge
dc.subjectGalaxy: structure
dc.subjectGalaxy: stellar content
dc.titleHow many components? Quantifying the complexity of the metallicity distribution in the Milky Way bulge with APOGEE
dc.typeartículo
dc.volumen499
sipa.indexWOS
sipa.trazabilidadWOS;2025-01-12
Files
Collections
Artículos de revistas