The Gaia -ESO Survey: radial distribution of abundances in the Galactic disc from open clusters and young-field stars

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

Context. The spatial distribution of elemental abundances in the disc of our Galaxy gives insights both on its assembly process and subsequent evolution, and on the stellar nucleogenesis of the different elements. Gradients can be traced using several types of objects as, for instance, (young and old) stars, open clusters, HII regions, planetary nebulae. Aims. We aim to trace the radial distributions of abundances of elements produced through different nucleosynthetic channels - the α-elements O, Mg, Si, Ca and Ti, and the iron-peak elements Fe, Cr, Ni and Sc - by use of the Gaia-ESO IDR4 results for open clusters and young-field stars. Methods. From the UVES spectra of member stars, we have determined the average composition of clusters with ages > 0.1 Gyr. We derived statistical ages and distances of field stars. We traced the abundance gradients using the cluster and field populations and compared them with a chemo-dynamical Galactic evolutionary model. Results. The adopted chemo-dynamical model, with the new generation of metallicity-dependent stellar yields for massive stars, is able to reproduce the observed spatial distributions of abundance ratios, in particular the abundance ratios of [O/Fe] and [Mg/Fe] in the inner disc (5 kpc <RGC< 7 kpc), with their differences, that were usually poorly explained by chemical evolution models. Conclusions. Oxygen and magnesium are often considered to be equivalent in tracing α-element abundances and in deducing, for example, the formation timescales of different Galactic stellar populations. In addition, often [α/Fe] is computed combining several α-elements. Our results indicate, as expected, a complex and diverse nucleosynthesis of the various α-elements, in particular in the high metallicity regimes, pointing towards a different origin of these elements and highlighting the risk of considering them as a single class with common features.

Detaljer

Författare
  • L. Magrini
  • S. Randich
  • G. Kordopatis
  • N. Prantzos
  • D. Romano
  • A. Chieffi
  • M. Limongi
  • P. François
  • E. Pancino
  • E. Friel
  • A. Bragaglia
  • G. Tautvaišiene
  • L. Spina
  • J. Overbeek
  • T. Cantat-Gaudin
  • P. Donati
  • A. Vallenari
  • R. Sordo
  • F. M. Jiménez-Esteban
  • B. Tang
  • A. Drazdauskas
  • S. G. Sousa
  • S. Duffau
  • P. Jofré
  • G. Gilmore
  • E. Alfaro
  • E. Flaccomio
  • S. Koposov
  • A. Lanzafame
  • R. Smiljanic
  • A Bayo
  • G. Carraro
  • A. R. Casey
  • M. T. Costado
  • F. Damiani
  • E. Franciosini
  • A. Hourihane
  • C. Lardo
  • J Lewis
  • L. Monaco
  • L. Morbidelli
  • G. G. Sacco
  • L. Sbordone
  • C. C. Worley
  • S. Zaggia
Enheter & grupper
Externa organisationer
  • INAF - Osservatorio Astrofisico di Arcetri
  • Leibniz Institute for Astrophysics Potsdam (AIP)
  • INAF Istituto di Astrofisica Spaziale e Fisica Cosmica, Bologna
  • INAF - Osservatorio Astronomico di Padova
  • INAF-Osservatorio Astronomico di Roma
  • Indiana University
  • Vilnius University
  • University of São Paulo
  • University of Padova
  • Suffolk University
  • University of Concepción
  • Pontifical Catholic University of Chile
  • CSIC Instituto de Astrofísica de Andalucía (IAA)
  • INAF Palermo Astronomical Observatory
  • University of Catania
  • Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences
  • University of Valparaíso
  • Max Planck Institute for Astronomy
  • European Southern Observatory Santiago
  • Liverpool John Moores University
  • Andrés Bello National University
  • Pierre and Marie Curie University
  • Paris Observatory
  • ASI Science Data Center
  • CSIC Centro de Astrobiologia (INTA)
  • University of Porto
  • Millennium Institute of Astrophysics
  • University of Cambridge
  • Diego Portales University
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Astronomi, astrofysik och kosmologi

Nyckelord

Originalspråkengelska
ArtikelnummerA2
TidskriftAstronomy and Astrophysics
Volym603
StatusPublished - 2017 jul 1
PublikationskategoriForskning
Peer review utfördJa