Aluminium-enriched metal-poor stars buried in the inner Galaxy

José G. Fernández-Trincado, Timothy C. Beers, Dante Minniti, Baitian Tang, Sandro Villanova, Doug Geisler, Angeles Pérez-Villegas, Katherine Vieira

Resultado de la investigación: Contribución a una revistaArtículorevisión exhaustiva

7 Citas (Scopus)

Resumen

Stars with higher levels of aluminium and nitrogen enrichment are often key pieces in the chemical makeup of multiple populations in almost all globular clusters (GCs). There is also compelling observational evidence that some Galactic components could be partially built from dissipated GCs. The identification of such stars among metal-poor field stars may therefore provide insight into the composite nature of the Milky Way (MW) bulge and inner stellar halo, and could also reveal other chemical peculiarities. Here, based on APOGEE spectra, we report the discovery of 29 mildly metal-poor ([Fe/H] -0.7) stars with stellar atmospheres strongly enriched in aluminium (Al-rich stars: [Al/Fe] +0.5), well above the typical Galactic levels, located within the solar radius toward the bulge region, which lies in highly eccentric orbits (e 0.6). We find many similarities for almost all of the chemical species measured in this work with the chemical patterns of GCs, and therefore we propose that they have likely been dynamically ejected into the bulge and inner halo from GCs formed in situ and/or GCs formed in different progenitors of known merger events experienced by the MW, such as the Gaia-Sausage-Enceladus and/or Sequoia.

Idioma originalInglés
Número de artículoL4
PublicaciónAstronomy and Astrophysics
Volumen643
DOI
EstadoPublicada - 1 nov 2020

Áreas temáticas de ASJC Scopus

  • Astronomía y astrofísica
  • Ciencias planetarias y espacial

Huella

Profundice en los temas de investigación de 'Aluminium-enriched metal-poor stars buried in the inner Galaxy'. En conjunto forman una huella única.

Citar esto